Hi,

I have an Excel workbook with macros and VBA code I was using in Office 2016 and Windows 7 fine.
I'm now moving to Windows 10 and encountering strange behaviour.

On Windows 10 with Office 2016, initially the workbook was being corrupted by Excel.
It ketp saying it had found errors in the file whenever I tried to save it.

I then saved the workbook as a standard xls file and then copied back in the VBA code bit by bit.
It appears as if there is some kind of bug with Office 2016 / 19 and user forms on Windows 10.
The error messages and crashes start occuring when I try to add back in a user form into my VBA project. However, Excel also crashes sometimes when I create a user form in a blank workbook.
I've tried running the workbook on two different Windows 10 machines (32bit and 64bit).

The error messages I'm getting include:
"name conflicts with existing module, project or object library" and when I get this message, it keeps appearing on screen every time I click on the Ok button and have to terminate Excel via the task manager. There's nothing else I can do.
"error loading dll" which appeared when I clicked on a form a few times
"out of memory" which I get sometimes when opening the VBA editor

I've searched online and think it may have something to do with the dll, "FM20.DLL". There doesn't seem to be any solutions that I've found.
I've tried deregistering and reregistering it using the command prompt but it hasn't helped.

I was using office 2016 but have just upgraded to office 2019 to see if there would be any change but am still getting the exact same behaviour on Windows 10.

Any help would be appreciated. I'm not sure what else to do. The workbook opens and runs without any issues on Windows 7.



Thanks