It could be some kind of permission issue related to UAC and folder or file security, or it could have something to do with any anti malware software taht might be on the system.
I suppose you could try temporarily turning off UAC to see if that fixes the problem. That would at least give you some idea of the cause and suggest some possible workarounds. You may also want to check the file (both .exe and .cmp) and folder permissions to make sure you have Read, Write, and Modify access.
So much has changed in both Windows and WinBatch in the last 12+ years that any suggestions are little more than somewhat educated guesses.