This is possibly the ugliest code I have ever seen. The comments essentially obfuscate the code and the indentation is semi-random. I suggest you get a copy of Perltidy and run the code through it with the -dbc option to delete the comments and fix the indentation, that way you can actually see the code and control logic. As it stands it is essentially unreadable and unmaintainable.

If you search for the error message "Can't open the file" you will find the if(@did_not_save) that triggers it. Go and find where @did_not_save is set and you will see the logic that makes this happen. Observe that the error message filename and the name of the file being opened are different, fix that, get a useful error message......