Combo ransomware: what it is and how to remove it

You cannot open them by renaming or by choosing another program. The .combo ending shows that Combo ransomware encrypted the content, and only the matching key can reverse it. Renaming a file back to .docx or .jpg changes nothing except the icon, and it can confuse a future decryptor, so leave the names as they are.

To get the content back, use a backup, an unencrypted copy elsewhere, or a decryptor listed on No More Ransom if one exists for Combo ransomware. Store the encrypted files on an external disk until then.

We last checked on 6 October 2026, and for Combo 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 "Combo 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.

We do not know yet. Nothing published so far shows data theft by Combo ransomware, but the only confirmed sign is files that end in .combo 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.

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.

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.

The way Combo 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 .combo 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.

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.

You can try it on a copy, but for real ransomware it will not help. The .combo extension is only a label; the file content has been scrambled with a key the attackers hold.

If a renamed copy opens normally, the malware only renamed files, which happens with some fake ransomware, and you can rename the rest back. If it does not open, leave the files as they are. Renaming encrypted files can confuse a decryptor later, so always work on copies.

Ransomware often runs at night or when the PC is idle, so the encryption finishes before anyone notices. It usually entered earlier through a cracked program, a fake installer, an e-mail attachment or remote desktop with a weak password.

The .combo extension marks every file it reached. Start by disconnecting the PC from the network, then identify the family from the ransom note and one encrypted file, check for a decryptor, and look for copies in backups and OneDrive before you consider anything else.

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 Combo 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.