Error when opening .sql files

Have a user running Toad for DB2 6.1.0.134. When they open a .sql file it yields the following error msg:

Not really sure where to begin with troublshooting this. Maybe someone in this forum has seen this before?

I was able to resolve the issue by renaming the 'Quest Software' folder in the "appdata\local" and "appdata\roaming" folders in the user's Windows profile. Assuming there some junk settings in them, and default settings resolved the issue.