No one wants to run a security program that uses false positives. When a scanner picks up false infections it can mean two things; first, the files are not on a computer at all or second, the files are non-malicious. Some fake security tools supposedly detect fake infections in order to attract customers. However, even legitimate software sometimes contains errors that lead into dealing with false positives.
Tuesday updates on AVG anti-virus caused the scanner to detect User32.dll file as it was related to PSW.Banker4.APSA trojan. Not only it is a false positive, but it is also an important component of Windows operating system. AVG users are strongly recommended to update the program as soon as possible. The error is fixed on the later updates of the software.
Those who ran a scanner after downloading the corrupted update were prompted to delete user32.dll. The absence of this file doesn’t cause any visible damage on Windows Vista, but the machines running Windows XP were reported to have boot issues. The missing user32.dll may be restored from c:\windows\system32\dllcache once you boot from a CD or run system recovery.