Office 2016 crashes when userform added to VBA.

This has (at least temporarily) solved the issue for my 3 users. They are able to close and reopen excel without further errors occurring. They have not yet logged out of and back into their devices so will update if the issue resurfaces.

Fixed!!!!

This is a bug in the install process I believe. The FM20.DLL creates an Excel.Box file which holds the configuration of the userform tool box for excel.

If missing this box file or using one created from and older version of this FM20.DLL is the culprit, say from an Office 2007 FM20.DLL. Additionally, it is possible a missing FM20.DLL in the SYSWOW64 folder did not allow the creation of the proper box file.

 

Resolution: I copied my current Windword.BOX and Excel.BOX files from my Windows 7 device (known working without issues) to my Windows 10 and that fixed the issue. Note: My Windows 7 and Windows 10 are both running Office 2016.

 

Deleting the box file as suggested in some forums does not work. Excel will just create a new default box file that is incompatible in my case.

  

This is a real issue many people are experiencing with no resolution from Microsoft and perhaps this information I provided above will help Microsoft sort out a fix

Deleting the box file as suggested in some forums does not work. Excel will just create a new default box file that is incompatible in my case. 

I just renamed my Excel.BOX file. When Excel created a new one and the form worked again, I deleted the old file. So for me the delete option worked.

Thanks Troubled Jackal!

Glad to hear that resolved your issue. Can you open a new intense of excel and create a new user form without a crash? If so then that's great.

With your suggestion, mine will work one time then the next time will crash.

Think this issue behavior will vary depending on the install and configuration. For me, I think the FM20.DLL is bad/older version that creates a corrupted/incompatible box file.

Replacing the box file with a known working one did the trick for me.

Thanks for your reply

Can you open a new intense of excel and create a new user form without a crash? 

Yes, appears so.

Great! sounds like you are good to go.

For more insight, do you have a FM20.DLL in your Main system folder: SYSWOW64 or SYS32?

On my Windows 7 that works fine, I do but on the Windows 10, I do not.

Also this file exists in Programdata/App-V location as well on both devices.

This file version is different on both machines and locations. I suspect FM20.DLL file has something to do with creating the box files, not completely sure. Perhaps initially from the system folder which I am missing. Your guess is better than mine.

My Windows 10 is a newer Office 365 build than my Windows 7.

Crash logs point to this FM20.dll file/could not find, before I applied my workaround fix.

C:\Program Files (x86)\Microsoft Office\root\vfs\SystemX86\
FM20.DLL
FM20ENU.DLL

Thanks for sharing those tips. 

I rencently upgraded from Office 2010 to Office 2016 and could not use most of my VBA forms anymore (crashing Outlook in FM20.dll).

In my case deleting the "Outlook.box" file in "AppData\Roaming\Microsoft\Forms" was good enough to solve the issue.

Thanks,