Excel prompts you to grant access to files and then hangs or shows a warning that it cannot open the .xlsx file because the format or extension is not valid

Last Updated: June 11, 2019

ISSUE

You may receive an unexpected prompt to Grant Access to files when you try to open a file or do "Save as..." or "Save a copy". When this happens, Excel may become unresponsive and you will need to force quit the application to recover.

STATUS: WORKAROUND

We are investigating this issue, but you may work around the problem by following these steps:

  1. Quit Excel.

  2. Go to Finder on your Mac.

  3. Press SHIFT+CMD+G and paste this folder path into the Go Todialog: ~/Library/Containers/com.microsoft.Excel/Data/Library/Preferences

  4. Select OK to go to the folder.

  5. Find the file called com.microsoft.Excel.securebookmarks.plist and move it to the Trash.

  6. Restart Excel.