Tcbu ransomware: what it is and how to remove it

Tcbu ransomware infections are not easily noticed because these particular threats can be distributed using other malware pieces like trojans and info-stealers. the infection process is silent and quick, so a particular virus payload is injected into the machine when the file attachment with the malicious file is opened, pirating package gets downloaded, or the particular tool launches the drop of the malware.

Facts checked October 7, 2026. Removal steps tested on Windows 11 (26H2) and checked against Microsoft's and the browser makers' current documentation. Sections marked as our earlier report are the original text: they describe the threat as it was then and have not been reviewed since. The 2026 status, the removal steps and the questions are current.

Automatic

Get a free scan and check if your PC is infected.

Fortect finds malware, unwanted programs and the Windows damage they leave behind, and repairs it in one pass.

Make sure nothing will rename more files to .tcbu: an automatic scan checks the PC first.

Remove it nowTo use the full-featured product, you have to purchase a license for Fortect. The scan is free.

Do it yourself · free Remove Tcbu ransomware yourself 6 steps, about 18 minutes, no software needed.

Start the steps
Screenshot of Tcbu ransomware: screenshot
Tcbu ransomware as our 2022 report showed it.

Tcbu ransomware: summary

DistributionFiles get distributed via emails, other threats and pirating services online
NameTcbu ransomware
TypeCryptovirus, file-locker
File marker.tcbu
Ransom amount$490/$980
Ransom note_readme.txt; the text of the note is not in our records
Removal

Scan the PC with security software to find and remove the malware and anything installed with it. Fortect scans Windows for malware and repairs the system files and settings it damaged.

Remove it nowTo use the full-featured product, you have to purchase a license for Fortect. The scan is free.
Show 12 more facts
Contact mailssupport@fishmail.top, datarestorehelp@airmail.cc
Detection namesNo Microsoft detection name is known
Encrypted file extension.tcbu
DecryptorNo free decryptor is known for this variant; check No More Ransom (nomoreransom.org) for updates
DamageNot recorded in the old report
SymptomsFiles renamed with a new extension and a ransom note left in folders
Evidence4 write-ups by security sites; no sample analysed yet
Encrypted files.tcbu
Attacker contactssupport@fishmail.top
Free decryptorNo free decryptor is known (checked 7 October 2026)
First seen21 November 2022
Facts checked7 October 2026
  • File extension: .tcbu
  • Note file: _readme.txt
  • Contact: support@fishmail.top

From our report of Nov 2022 · not reviewed since

More from our earlier report on Tcbu ransomware

  • Rely on threat removal tools and security programs like or to terminate this virus
  • The infection can damage parts of the machine, so run to fix related issues with corrupted system

How Tcbu ransomware behaves

From our report of Nov 2022 · not reviewed since

Tcbu ransomware is a threat that can be spread alongside other threats

Tcbu ransomware infections are not easily noticed because these particular threats can be distributed using other malware pieces like trojans and info-stealers. the infection process is silent and quick, so a particular virus payload is injected into the machine when the file attachment with the malicious file is opened, pirating package gets downloaded, or the particular tool launches the drop of the malware.

Tcbu file virus can be intrusive and damaging, but it manages to mask these issues with other pop-ups, so people only see the data locked and marked using .tcbu appendix. The infection encodes commonly used files and uses powerful encryption methods for this.

Then the ransom note can be dropped where virus creators can ask for the payments in exchange for the alleged decryption tool delivery. However, that is rarely happening because threat actors are commonly disappearing instead of providing the victim with a working tool for the Tcbu ransomware virus files.

Screenshot of Tcbu ransomware: screenshot
Tcbu ransomware in our 2022 report.

From our report of Nov 2022 · not reviewed since

The dangerous family of threats

Tcbu ransomware comes after the 600 other versions of Djvu virus that were released throughout these years since the first 2018 release.

It is known that the infection is using other malware to spread the ransomware payload around. Pirating packages and malicious file attachments can be used in these campaigns.

The threat is injected into the machine silently, and encryption processes can happen. Tcbu file virus can employ malware like information stealers Vidar and RedLine to trigger the launch of the payload. The infection can be triggered when people download these files from torrent services unknowingly and when they open a malicious file attachment from emails too.

You need to check those pieces before you go for the download, so you can avoid an infection like Tcbu ransomware virus. Unfortunately, distribution is not the only thing evolved and advanced with these recent versions. Encryption is also more powerful with these releases that are weekly at this time, as experts note.

The threat uses online IDs right now, and those are unique for each device that the virus affects. Previously used offline keys were uniform for all the devices that get encrypted by one version, so tools were developed based on that method. Right now, it is less common that Tcbu ransomware will use offline keys, but you can still try to decrypt these files.

Tcbu ransomware: tcbu ransom note
The message as our 2022 report captured it.

The Tcbu ransomware note

The note is called _readme.txt.

We did not record the full text of the ransom note in our report.

How to remove Tcbu ransomware

Tools you'll need

All of these are free except where noted. Download them on a clean device if the infected PC is offline.

  • A USB stick: to keep the ransom note, two or three encrypted files and screenshots off the infected PC.
  • Microsoft Defender Offline: built into Windows 11 and Windows 10; scans before Windows starts, so running malware cannot hide.
  • Microsoft Safety Scanner: a second, portable scanner with current signatures; each download works for 10 days.
  • ID Ransomware: identifies the family from the note and one encrypted file and says whether a decryptor exists.
  • No More Ransom: the free decryptors from police and security companies; check it again every few months.
  • Fortect (optional): scans Windows for malware and repairs the system files and settings it damaged. The free scan is in the box above.

How to remove Tcbu ransomware and get your files back

Work in this order.

Disconnecting comes first, removal comes before any restore, and nothing here asks you to contact the attackers.

  1. Step 1: Disconnect the PC and unplug backup drives

    Unplug the network cable or turn off Wi-Fi, and disconnect USB drives, external disks and network shares, so Tcbu ransomware cannot reach more files. Pause OneDrive, Google Drive or Dropbox sync, because synced folders upload the encrypted copies over the good ones.

    Leave the PC on but offline while you read the next steps, since a restart can let the ransomware run again. This applies to Windows 11 and Windows 10 alike.

    Windows 11 quick settings with Wi-Fi turned off
    Windows 11: turn off Wi-Fi to take the PC offline.

    Full procedure with screenshots: Ransomware: first steps, finding a decryptor and recovering files

  2. Step 2: Save the ransom note and confirm the family

    Your files now end in .tcbu and the instructions are in _readme.txt. Save both to a USB stick, a copy of the note and two small encrypted files, before anything else.

    On another device, check them with ID Ransomware or Crypto Sheriff: the family name decides which decryptor, if any, can help. Keep the note's ID and contact line for your report.

    A ransom note text file next to encrypted files in File Explorer
    Windows 11: the ransom note and encrypted files to copy for identification.

    Full procedure with screenshots: Ransomware: first steps, finding a decryptor and recovering files

  3. Step 3: Check for a free decryptor

    Our last check found that for Tcbu ransomware, no free decryptor is known (checked 7 October 2026). Look again yourself in the No More Ransom list and the free decryptor pages of Emsisoft, Avast and Kaspersky, which add new families every year.

    A decryptor needs the ransomware gone first, or it encrypts the files again. Keep at least one copy of the encrypted files on an external drive, even if no tool works yet.

    Full procedure with screenshots: Ransomware: first steps, finding a decryptor and recovering files

  4. Step 4: Remove the ransomware before you restore or decrypt

    Removing Tcbu ransomware does not bring the files back, but it has to come first. Start with Defender's Full scan, then the offline scan from the same Scan options page, which checks the disk before Windows loads.

    If the scan cannot start, use Safe Mode with Networking. Delete the ransom notes only after you have saved a copy, because removal tools sometimes leave them behind on Windows 11 and Windows 10.

    Windows Security Scan options with Microsoft Defender Antivirus offline scan selected
    Windows 11: Windows Security > Virus & threat protection > Scan options.

    Full procedure with screenshots: Run a Microsoft Defender Offline scan

  5. Step 5: Look for shadow copies of the files

    Windows keeps shadow copies for restore points and backups, and some ransomware fails to delete them. vssadmin list shadows in an administrator Command Prompt tells you at once whether any exist.

    If they do, right-click the folder that held your files, open Properties > Previous Versions, select a version from before the attack, and click Open to check it before you Restore or copy the files out. Windows 11 and Windows 10 both have the tab.

    Command Prompt running vssadmin list shadows
    Windows 11: vssadmin list shadows shows whether shadow copies exist.

    Full procedure with screenshots: Ransomware: first steps, finding a decryptor and recovering files

  6. Step 6: Restore the files from a backup or recover deleted originals

    A backup made before the attack is the surest way back. Connect it only once the PC is clean, then restore from File History, Windows Backup, OneDrive's Restore your OneDrive or your own external copies.

    Without a backup, try file recovery: the originals that Tcbu ransomware deleted may still be on the disk until something overwrites them. Install nothing new on the drive you want to recover from on the Windows 11 or Windows 10 PC.

    Full procedure with screenshots: Recover deleted files (Recycle Bin, backups, OneDrive) On uGetFix

Instructions for each browser and system

The detailed steps for every browser and system this guide covers. Open the one you use.

Restore Windows "hosts" file to its original state

Some ransomware might modify Windows hosts file in order to prevent users from accessing certain websites online. For example, Djvu ransomware variants add dozens of entries containing URLs of security-related websites, such as 2-spyware.com. Each of the entries means that users will not be able to access the listed web addresses and will receive an error instead.

Here's an example of "hosts" file entries that were injected by ransomware:

Hosts file

In order to restore your ability to access all websites without restrictions, you should either delete the file (Windows will automatically recreate it) or remove all the malware-created entries. If you have never touched the "hosts" file before, you should simply delete it by marking it and pressing Shift + Del on your keyboard. For that, navigate to the following location:

C:\\Windows\\System32\\drivers\\etc\\

Delete Windows "hosts" file

Manual removal using Safe Mode

Important! →
Manual removal guide might be too complicated for regular computer users. It requires advanced IT knowledge to be performed correctly (if vital system files are removed or damaged, it might result in full Windows compromise), and it also might take hours to complete. Therefore, we highly advise using the automatic method provided above instead.

Step 1. Access Safe Mode with Networking

Manual malware removal should be best performed in the Safe Mode environment.

Windows 7 / Vista / XP

  1. Click Start > Shutdown > Restart > OK.
  2. When your computer becomes active, start pressing F8 button (if that does not work, try F2, F12, Del, etc. - it all depends on your motherboard model) multiple times until you see the Advanced Boot Options window.
  3. Select Safe Mode with Networking from the list.Windows 7/XP

Windows 10 / Windows 8

  1. Right-click on Start button and select Settings.
    Settings
  2. Scroll down to pick Update & Security.
    Update and security
  3. On the left side of the window, pick Recovery.
  4. Now scroll down to find Advanced Startup section.
  5. Click Restart now.
    Reboot
  6. Select Troubleshoot.Choose an option
  7. Go to Advanced options.Advanced options
  8. Select Startup Settings.Startup settings
  9. Press Restart.
  10. Now press 5 or click 5) Enable Safe Mode with Networking.Enable safe mode

Step 2. Shut down suspicious processes

Windows Task Manager is a useful tool that shows all the processes running in the background. If malware is running a process, you need to shut it down:

  1. Press Ctrl + Shift + Esc on your keyboard to open Windows Task Manager.
  2. Click on More details.
    Open task manager
  3. Scroll down to Background processes section, and look for anything suspicious.
  4. Right-click and select Open file location.
    Open file location
  5. Go back to the process, right-click and pick End Task.
    End task
  6. Delete the contents of the malicious folder.

Step 3. Check program Startup

  1. Press Ctrl + Shift + Esc on your keyboard to open Windows Task Manager.
  2. Go to Startup tab.
  3. Right-click on the suspicious program and pick Disable.
    Startup

Step 4. Delete virus files

Malware-related files can be found in various places within your computer. Here are instructions that could help you find them:

  1. Type in Disk Cleanup in Windows search and press Enter.
    Disk cleanup
  2. Select the drive you want to clean (C: is your main drive by default and is likely to be the one that has malicious files in).
  3. Scroll through the Files to delete list and select the following: Temporary Internet Files
    Downloads
    Recycle Bin
    Temporary files
  4. Pick Clean up system files.
    Delete temp files
  5. You can also look for other malicious files hidden in the following folders (type these entries in Windows Search and press Enter): %AppData%
    %LocalAppData%
    %ProgramData%
    %WinDir%

After you are finished, reboot the PC in normal mode.

Important steps to take before you begin malware removal

File encryption is one component of a ransomware infection, which may also include credential theft, persistence mechanisms, and lateral movement. However, it is important to understand that malware may perform various changes within a Windows operating system, including persistence, scheduled tasks, registry modifications, and security feature tampering.

IMPORTANT for those without backups! →
If you attempt to use security or recovery software immediately, you might permanently damage your files, and even a working decryptor then would not be able to save them.

Before you proceed with the removal instructions below, you should copy the encrypted files onto a separate medium, such as USB flash drive or SSD, and then disconnect them from your computer. The storage device should remain disconnected after copying to prevent accidental modification or deletion. Encrypted data itself does not contain active malicious code, but only the encrypted files—not executables or scripts—should be transferred.

The instructions below might initially seem overwhelming and complicated, but they are not difficult to understand as long as you follow each step in the appropriate order. This comprehensive free guide will help you to handle the malware removal and data recovery process correctly.

If you have any questions, comments, or are having troubles with following the instructions, please do not hesitate to contact us via the Ask Us section.

IMPORTANT! →
It is vital to eliminate malware infection from the computer fully before starting the data recovery process, otherwise ransomware might re-encrypt retrieved files from backups repeatedly.

Restore files using data recovery software

Since many users do not prepare proper data backups prior to being attacked by ransomware, they might often lose access to their files permanently. Paying criminals is also very risky, as they might not fulfill the promises and never send back the required decryption tool.

While this might sound terrible, not all is lost - data recovery software might be able to help you in some situations (it highly depends on the encryption algorithm used, whether ransomware managed to complete the programmed tasks, etc.). Since there are thousands of different ransomware strains, it is immediately impossible to tell whether third-party software will work for you.

Therefore, we suggest trying regardless of which ransomware attacked your computer. Before you begin, several pointers are important while dealing with this situation:

  • Since the encrypted data on your computer might permanently be damaged by security or data recovery software, you should first make backups of it - use a USB flash drive or another storage.
  • Only attempt to recover your files using this method after you perform a scan with anti-malware software.

Install data recovery software

  1. Download .
  2. Double-click the installer to launch it.
  3. Follow on-screen instructions to install the software.Install program
  4. As soon as you press Finish, you can use the app.
  5. Select Everything or pick individual folders where you want the files to be recovered from.Select what to recover
  6. Press Next.
  7. At the bottom, enable Deep scan and pick which Disks you want to be scanned.Select Deep scan
  8. Press Scan and wait till it is complete.Scan
  9. You can now pick which folders/files to recover - don't forget you also have the option to search by the file name!
  10. Press Recover to retrieve your files.Recover files
Create data backups to avoid file loss in the future
Report the incident to your local authorities

Ransomware is a lucrative, highly illegal business, and authorities are actively targeting ransomware operators. The level of investigation and follow-up depends on the country, the scale of the incident, and whether the attack is linked to known ransomware groups. To increase the likelihood of identifying the culprits, the agencies need information. In many cases, reports are used primarily for intelligence gathering, trend analysis, and victim support rather than immediate identification of attackers.

Therefore, by reporting the crime, you could help stop the cybercriminal activities and catch the threat actors. Reporting does not guarantee investigation or recovery of data, but it contributes to broader efforts to track ransomware campaigns. Make sure you include all the possible details, including how did you notice the attack, when it happened, etc. Relevant details may also include affected systems, ransom demands, cryptocurrency wallet addresses, and any communication with the attackers. Additionally, providing documents such as ransom notes, encrypted files, or malware executables would be beneficial.

Law enforcement agencies typically deal with online fraud and cybercrime, although it depends on where you live. Here is the list of local authority groups that handle incidents like ransomware attacks, sorted by country:

  • USA - Internet Crime Complaint Center IC3
  • United Kingdom - ActionFraud
  • Canada - Canadian Anti-Fraud Centre
  • Australia - ScamWatch
  • New Zealand - ConsumerProtection
  • Germany - Polizei
  • France - Ministère de l'Intérieur

Internet Crime Complaint Center IC3

If your country is not listed above, you should contact the local police department or communications center.

From our report of Nov 2022 · not reviewed since

The decryption of the malware

If your computer got infected with one of the Djvu variants, you should try using Emsisoft decryptor for Djvu/STOP.

It is important to mention that this tool will not work for everyone - it only works if data was locked with an offline ID due to malware failing to communicate with its remote servers.

Even if your case meets this condition, somebody from the victims has to pay criminals, retrieve an offline key, and then share it with security researchers at Emsisoft. As a result, you might not be able to restore the encrypted files immediately.

Thus, if the decryptor says your data was locked with an offline ID but cannot be recovered currently, you should try later. You also need to upload a set of files - one encrypted and a healthy one to the company's servers before you proceed.

From here, there are three available outcomes:

  • After pressing Download button, a small pop-up at the bottom, titled decrypt_STOPDjvu.exe should show up - click it.
  • If User Account Control (UAC) message shows up, press Yes.
  • Agree to License Terms by pressing Yes.
  • After Disclaimer shows up, press OK.
  • The tool should automatically populate the affected folders, although you can also do it by pressing Add folder at the bottom.
  • Press Decrypt.
  • "Decrypted!" will be shown under files that were decrypted successfully - they are now usable again.
  • "Error: Unable to decrypt file with ID:" means that the keys for this version of the virus have not yet been retrieved, so you should try later.
  • "This ID appears to be an online ID, decryption is impossible" - you are unable to decrypt files with this tool.
Screenshot of Tcbu ransomware: emsisoft1
Tcbu ransomware in our 2022 report.
Screenshot of Tcbu ransomware: emsisoft2
Tcbu ransomware in our 2022 report.

From our report of Nov 2022 · not reviewed since

Removing the infection

Tcbu ransomware is powerful and can be persistent in addition to its dangerous capabilities and damaging functions.

You must remove the virus if you want to use the machine ever again. Triggering the system scan when the AV detection tools like or get used can be problem-solving.

These threat detection tools can find malicious files on machines and all hidden pieces on the computer that are linked to this or other viruses. Tcbu file virus can be removed when it is listed as a potentially dangerous piece of malware after the system check.

The removal is not the same as decrypting the virus or recovering the data after the infection. Termination is important because the active virus that is still running on the machine can locate any new files and encrypt them. Tcbu ransomware virus is also capable of encrypting files again.

Permanent damage can be caused by these encryption procedures that get repeated. The sooner you remove the threat, the better because this virus is no longer running and messing with anything you possibly remove. Also, encryption is the first step of the Tcbu ransomware, so the sooner you remove and stop it, the bigger opportunity to avoid further issues and system damage there is.

From our report of Nov 2022 · not reviewed since

System file recovery

Once a computer is infected with malware, its system is changed to operate differently.

For example, an infection can alter the Windows registry database, damage vital bootup and other sections, delete or corrupt DLL files, etc. Once a system file is damaged by malware, antivirus software is not capable of doing anything about it, leaving it just the way it is. Consequently, users might experience performance, stability, and usability issues, to the point where a full Windows reinstall is required.

Not only can it fix virus damage after the infection, but it is also capable of removing malware that has already broken into the system thanks to several engines used by the program. Besides, the application is also capable of fixing various Windows-related issues that are not caused by malware infections, for example, Blue Screen errors, freezes, registry errors, damaged DLLs, etc.

  • Download the application by clicking on the link above
  • Click on the ReimageRepair.exe
  • If User Account Control (UAC) shows up, select Yes
  • Press Install and wait till the program finishes the installation process
  • The analysis of your machine will begin immediately
  • Once complete, check the results - they will be listed in the Summary
  • You can now click on each of the issues and fix them manually
Tcbu ransomware: 1 1
Tcbu ransomware in our 2022 report.
Tcbu ransomware: 2 2
Tcbu ransomware in our 2022 report.

Report it and recover your files

Report it

Report the attack even if you do not expect the files back: insurers and banks ask for the report number, and police use the contacts in the note to link cases.

United States
FBI IC3 · FTC ReportFraud

Give the victim ID, the note and the date the files were encrypted. A business that holds personal data may also have to notify its data protection authority, in the EU within 72 hours.

Backups: the 3-2-1 rule

Keep three copies of files that matter, on two kinds of storage, with one copy offline or off-site.

A disk that stays plugged in is reached by malware like Tcbu ransomware together with the PC; one you connect only for the backup is not.

On Windows 11, File History keeps versions on an external drive, and OneDrive keeps earlier versions of synced files. Before restoring anything, make sure the PC no longer shows files that end in .tcbu and no longer open.

Setting it up step by step: 3-2-1 backups on Windows 11 and 10.

Stream videos without limitations, no matter where you are

There are multiple parties that could find out almost anything about you by checking your online activity.

While this is highly unlikely, advertisers and tech companies are constantly tracking you online. The first step to privacy should be a secure browser that focuses on tracker reduction to a minimum.

Even if you employ a secure browser, you will not be able to access websites that are restricted due to local government laws or other reasons. In other words, you may not be able to stream Disney+ or US-based Netflix in some countries. To bypass these restrictions, you can employ a powerful VPN, which provides dedicated servers for torrenting and streaming, not slowing you down in the process.

Data backups are important - recover your lost files

Ransomware is one of the biggest threats to personal data.

Once it is executed on a machine, it launches a sophisticated encryption algorithm that locks all your files, although it does not destroy them. The most common misconception is that anti-malware software can return files to their previous states. This is not true, however, and data remains locked after the malicious payload is deleted.

While regular data backups are the only secure method to recover your files after a ransomware attack, tools such as can also be effective and restore at least some of your lost data.

Questions about Tcbu ransomware

How do I open .tcbu files?

You cannot open them by renaming or with another program, because the content of files ending in .tcbu has been encrypted. The only ways back are a working decryptor for the family, or clean copies from elsewhere:

  • OneDrive versions
  • File History
  • an offline backup drive
  • Previous Versions if the ransomware did not delete them

Identify the family first by uploading the ransom note and one encrypted file to ID Ransomware or No More Ransom. Avoid websites and programs that promise to open any encrypted file; they do not work and some are scams.

Is there a free Tcbu ransomware decryptor?

We last checked on 7 October 2026, and for Tcbu ransomware no free decryptor is known. We check No More Ransom, which collects free tools from police and security companies, and the decryptor pages of the major antivirus vendors. A working decryptor exists only when the encryption has a flaw or the keys were leaked or seized.

Ignore sites and videos that offer a "Tcbu ransomware decryptor" for download or for a fee: these are usually scams or malware. Real decryptors are free and come from known security companies or law enforcement. Keep the encrypted files in case a tool appears later.

Should I pay the ransom?

We advise against it, and so do the FBI, Europol and national cyber agencies. Payment does not guarantee a working tool: some attackers never reply, some tools damage files, and some variants have no decryptor at all. Paying also funds further attacks and can make you a target again.

Before considering payment, try every recovery option in this guide and report the attack. Companies must involve their legal adviser and insurer, because payments to sanctioned groups can be illegal. If files are truly irreplaceable, store the encrypted copies and wait; decryptors sometimes appear later.

Are ransomware recovery services legitimate?

Some are, but read the offer carefully. Genuine data-recovery firms recover deleted originals from disks or rebuild damaged files, and they say so. Others promise to "decrypt any ransomware" for a fixed price, which is impossible without the key; they quietly pay the attackers and keep a margin, sometimes without telling the victim.

Be especially careful with services that contact you after you post about the attack online. Ask for references, a written method and a no-result-no-fee clause, and check the free tools on No More Ransom first.

How did Tcbu ransomware get on my computer?

The way Tcbu ransomware spreads has not been documented yet, so look at your own recent activity. On home PCs, ransomware most often comes with cracked programs, game cheats, key generators and fake updates, or with an e-mail attachment that was opened. On business networks, attackers usually log in through Remote Desktop with a stolen or guessed password.

Think back to what was downloaded or installed in the days before files that end in .tcbu and no longer open, and check the Downloads folder and Installed apps sorted by date. Keep anything suspicious for your report, but do not run it again.

Did Tcbu ransomware steal my files or passwords?

We do not know yet. Nothing published so far shows data theft by Tcbu ransomware, but the only confirmed sign is files that end in .tcbu and no longer open, which says nothing about what happened before. Many current ransomware attacks copy files or run a password stealer first, so it is wise to act as if they did.

From a clean device, change the passwords that were saved in the browsers on this PC, starting with e-mail and banking, sign out of all sessions and turn on two-step verification. Watch bank statements and account activity for the next few weeks.

Is Tcbu ransomware the same as other ransomware with a similar name?

Not necessarily. Ransomware names come from the file extension, the note or a word in the code, so unrelated families often end up with similar names, and one family can appear under several names. The difference matters: a decryptor or advice for one family does not fit another and can damage files.

Compare the ending added to your files and the exact name of the note with the summary table at the top of this guide, then upload the note and one encrypted file to ID Ransomware from a clean device. If the result names another family, follow the guide for that family instead.

Should I open _readme.txt?

Reading it is fine if you open it in Notepad. A plain text _readme.txt cannot harm the PC. Be careful with notes in HTA or HTML format: double-clicking those runs them in a window that can contain scripts, so right-click and choose Open with > Notepad instead.

The note tells you the contact addresses, the claimed amount and the deadline. Do not visit links or write to the addresses from this PC. Use the note to identify the family and check for a free decryptor first.

Will .tcbu spread to my other drives?

It can. Ransomware encrypts every drive and network share it can reach while it runs, so external disks, USB sticks and shared folders connected during the attack may also have files ending in .tcbu. Disconnect everything now, then check each device from a clean computer.

Do not plug a backup drive into the infected PC until the ransomware has been removed with an offline scan. Cloud folders such as OneDrive sync the encrypted versions, but they keep earlier versions you can usually restore.

Will Fortect remove Tcbu ransomware?

Fortect scans Windows for malware and unwanted programs and repairs the system files and settings they change, and its free scan shows what it finds on your PC before you decide anything.

For Tcbu ransomware, follow the plan above as well: the browser steps take back permissions and settings that no scanner treats as a threat, and uninstalling the program that brought it removes the source.

Run Microsoft Defender's full scan and, if anything was found, its offline scan as a second opinion. If the symptoms are gone after the plan and both scans are clean, there is nothing more to do.

Sources

More removal guides

Questions and experiences: Tcbu ransomware

Still seeing it, or found something we did not cover? Ask here: members and our editors answer. Reading is open; writing needs a free account.

0 comments

…

5,441 members already hereReading, writing, commenting and voting. 0 verified · 166 joined this year