After running the program CRC32 checks the external compression utility UPX.EXE if the checksum does not match there is a suspicion of content corruption or file infection. An information message is displayed about this error the utility is deleted and newly generated from the internal storage which is part of the program. The program will then start normally.


If the infected file cannot be deleted the file is already protected by the infected OS and you need to use your antivirus program to resolve this. Therefore the UPX .EXE Compressor program deactivates all options associated with the use of this utility and these remain inactive until the problem of the infected file is resolved (deleted) and the program is restarted. The program regenerates the utility from the internal storage and then starts normally.


Furthermore the program is protected by RunInIDE technology against unwanted modification.