If you have no .VBA files at all in the GP directory, then I'd try the following on one of the machines that has GP on it seeing this issue with crashing:
1. On one of the machines where you have Dynamics GP installed, rename the GP directory from something like this >> C:\Program Files(x86)\Microsoft Dynamics\GP\ to be something like this >> C:\Program Files(x86)\Microsoft Dynamics\GP_OLD\
2. In Control Panel > Programs > Programs and Features, right-click on this instance of Microsoft Dynamics GP and click ‘Change’.
3. In the options window that opens, choose the ‘Repair’ option and verify the process runs successfully. This will re-create the entire Dynamics GP directory, to include all files and folders, under the original directory name that we just changed.
4. Launch Dynamics GP from this ‘new’ GP directory and login with the 'sa' login ideally to see whether or not you still see the issue with GP crashing when changing vendor email information. If you can, then you can also verify with other non-sa users to make sure they can as well.
--If users can change vendor email info with this 'new' Dynamics GP directory, then we'd want to add back any forms/reports dictionary files, third party products and/or customizations, one by one, testing after each one is added, to verify that you can still change the vendor email info without GP crashing. If the crashing issue returns, then we'd want to look at the last thing added back, which caused the crash to occur again.
The above would help rule out third parties or customizations.
If you have more than one machine with GP on it, we'd want to verify whether the crashing occurs on all machines or not, which would then seem to indicate something other than GP code and maybe more database related and/or user issues.