These errors usually happen because of broken restore point files, very tightly compressed archives, or leftover pieces of files in temporary folders.
1. Check for a Decompression Bomb
The main reason why you might see this error message is if Avast thinks a file being scanned is a ‘decompression bomb’ (sometimes called a zip bomb). A ‘decompression bomb’ is an archive file (such as a RAR or ZIP) that has been compressed to a very high degree. When such a file is decompressed, it can expand to hundreds or thousands of times its original size and use up all of your computer’s memory. These files are sometimes used in DoS (Denial-of-Service) attacks intended to overwhelm or crash antivirus programs. Most security tools recognize this risk and will refuse to scan or open suspicious archive files to protect your system. If you think this might be the case, the safest solution is to simply delete the file in question. If you downloaded the file from an untrustworthy source, remove it immediately from your computer. Then, run another boot-time scan with Avast at your next startup.
2. Disable and Re-Enable System Restore
Another possible reason for error codes like 42110 or 42125 is corruption in the system restore files. Thankfully, several users have reported that they were able to fix this problem by temporarily turning off System Restore, restarting their computer, and then turning System Restore back on. If you want to try this solution, follow these steps to disable and then re-enable System Restore to resolve Avast errors 42110 and 42125:
