Custom UI Not working in Select file

**Austin Martin** · 09-24-2021, 11:26 AM

Hello,

I have a really strange case that I cannot figure out (I'm using Excel 2016). I wrote a CustomUI Xml for changing the Backstage for one of my large Excel files used by many people. The Xml is correct and verified, but it makes no visible change within the macro-enabled workbook. However, if I copy the very same code to a completely different workbook and save it with the CustomUI tool, it works perfectly fine. It simply does not work in the workbook I need it to work in. Is there anything I can do to troubleshoot this? I tried changing the .xlsm file to a .zip file, deleting the CustomUI folder, and starting fresh; however this did not fix the issue.

**romperstomper** · 09-24-2021, 11:33 AM

Do you have the option to display add-in user interface errors enabled? That should at least alert you if something is going wrong when the customui loads.

**Austin Martin** · 09-24-2021, 11:42 AM

That is not enabled. I've checked it a few times now . . lol

**romperstomper** · 09-24-2021, 11:44 AM

You should enable it and then open your workbook.

**Austin Martin** · 09-24-2021, 11:46 AM

Okay I tried enabling that setting, then rebooting the file. I received this error message:
"Multiple custom UI parts were found in the file. Only one part is expected."

I know there is only one part in this file unless there is some corrupted part somewhere I am not seeing?

**Austin Martin** · 09-24-2021, 11:49 AM

Attachment 749092

This is what loads in CustomUI Tool. There is only the one CustomUI part in this file.

**romperstomper** · 09-24-2021, 11:59 AM

Those attachments don't work, so I can't see that. You have to click the Go Advanced button and then Manage attachments to upload the image properly.

**romperstomper** · 09-24-2021, 12:00 PM

Or just remove all the data and code from the file and then post it here.

**Austin Martin** · 09-24-2021, 12:02 PM

Here is the attachment now. The code itself I simply copied online for editing Backstage. There is only one CustomUI part in this workbook

**Austin Martin** · 09-24-2021, 12:16 PM

Okay after doing some digging and Googling, I have solved the issue. I had to open the .xlm file within the "_rls" folder in the Workbook innards. This xlm file had 3 different relationships for CustomUI files (There is only supposed to be 1). I deleted these three lines, then deleted the CustomUI. Swapped it back to a .xlsm file, added the CustomUI code back, and it magically worked . . . . . funny how Excel doesn't know how to fix its own issues.