Dear BDY1,
Good day! Thank you for posting to Microsoft Community. We are happy to help you.
As per your description, please don’t worry, we can work together to narrow down and resolve the situation.
Sometime the error message occurs if attempting to open contained a reference to an add-in file. And once removed users are able to open the file without any issues.
Since you mentioned when you try to open another ".xlsm*"* file and you got the same result, could you please try to use another way to open the file. Open Excel app> File > Open to open the file to check if there is any difference or not.
As the problem can be caused by different reason, I will appreciate you can try the normal troubleshooting steps 1 by 1 below and tell us the result.
1.First please try installing updates then test again. Update Office for Mac automatically - Office Support. The latest updates version is 16.63
2.Try to reboot Mac in safe mode and determine whether background programs are causing the issue. For detailed information, please check this article.
3.Have you ever installed any add-ins for Word? If so, please disable them and then check the outcomes.
4.Another suggestion is to remove the Office folders from Containers folder in Library with following steps.
a: Completely quit all Office apps
b: In Finder, press COMMAND +Shift+g.
c: Enter**~/Library** and click Go
d: Go to Containers folder, find the folder called Microsoft Word or com.Microsoft.Word
e: Move this folder to your desktop by cut&paste .
f: Relaunch Word for Mac application and see the results.
5.Also, I suggest starting by checking file system using Disk Utility. If there are file system problems, Disk Utility may be able to fix them.
How to repair a Mac disk with Disk Utility - Apple Support
Disclaimer: Microsoft provides no assurances and/or warranties, implied or otherwise, and is not responsible for the information you receive from the third-party linked sites or any support related to technology.
6.If the problem occurs to all Word file even newly created Word document file as well on your Mac OS, then I suspect components were corrupted somehow. You can go to the Applications folder In Finder and drag Microsoft Word.app to the trash. Then Restart your Mac Download this installer Install package Word and use it to reinstall Microsoft Word (the version 16.63). Then, restart your Mac and test.
If above suggestion does not work, to narrow down your issue, please tell us more information below to let us help you:
1. The version of Mac OS and Office
Find out which macOS your Mac is using
About Office: What version of Office am I using?
2.Can you recall when this behavior starts e.g., after Office update or Mac OS.
Your understanding and patience will be highly appreciated. I hope that you are keeping safe and well!
Sincerely,
Waqas Muhammad
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