Hmmm. I'm pretty well at a loss myself. I have two final suggestions.

1. Try renaming the controls to shorter names. That may have an impact.

2. Download, install, and run Rob Bovey's Code Cleaner on the file.
Sometimes when modules or userforms act strangely, they need to be "cleaned".
That is, the file is corrupted and should be exported and imported. Rob's
program automates this task. You can find it he

http://www.appspro.com/Utilities/CodeCleaner.htm

HTH,
Matthew Pfluger