There are times when running a function in Wall Worm brings up a message about an Unknown System Exception. This issue is known to happen in some of the file parsing functions like the VMF Importer and FGD Parser. It can also happen if there are corrupt utility files.

If you see this error while using the Entity Parser or VMF importer, the problem is detailed below. If this isn't the problem, see the corrupt utility files link above.

At this time, the culprit for this issue seems to be files with mixed EOL (end of line) and/or files that do not have EOL characters at the end of the file. It's related to a bug in MAXScript's filestream reader that is prone to errors with files that don't have expected line-endings.

If you encounter this problem, here are some steps you can take to make your file more compatible with Wall Worm:

1. Open the file in a text editor and add a line break at the very end of the file and Save.
2. If #1 doesn't work, open the text file in a text editor and convert all line endings to CRLF (Carriage Return + Line Feed). You can do this with Notepad++ by clicking EDIT > EOL Conversion > Windows.

Make sure you backup your file before trying option #2.

For the most part this issue has been alleviated from the VMF Importer. It's still reported to happen on occassion with the FGD Parser in standard WW. The FGD parser does not have this problem in WW Pro since the WW Pro uses an independent line reader that doesn't depend on the buggy MAXScript stream reader.

If you cannot upgrade to WW Pro and this problem is occuring when WW tries to parse the FGD, you can manually download and install the entity cache for some games on the Entity Cache docs.