Hi @II
Does this issue occur with new created Excel file and other Office files, such as Word document?
Which versions of Mac OS and Office for Mac are you using now?
To check the Office version, you may go to Excel, go to Excel menu, and click About Excel. It's recommended to update the Office to the latest one (16.86 (24060916).
Please try other folders/ different locations to save.
Then I suggest you remove the Excel cache and configuration file from the Library folder.
- Completely quit all Office applications
- In Finder, press Command +Shift + G and enter ~/Library to open Library folder.
- In the Library folder, open Containers folder and remove the folder “Microsoft.Excel”.
- Restart Mac and relaunch the Excel application to see the results.
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