Hi,
Did you install any updates for Windows or Office recently?
Did this problem only appear in Excel? How about other Office products?
Did you install any add-in for Excel recently?
Did you have any error messages when try to save as the Workbook?
I suggest you open it in safe mode running the following command: Press Win + R, type "excel /safe" in the blank box, press Enter. If it works fine in safe mode, please check the add-ins in your excel and disable them.
Click File > Excel Options > Add-Ins on the left side of the dialog. Then click the drop-down arrow at the bottom of the dialog box and select "COM Add-Ins" from the list, then click the GO button. What comes up is a list of COM-Add Ins that are loaded and running.
You can also go to File- Options- Save, please confirm if the default save file location is correct:
Just checking in to see if the information was helpful. Please let us know if you would like further assistance.
If the response is helpful, please click "Accept Answer" and upvote it.
Note: Please follow the steps in our documentation to enable e-mail notifications if you want to receive the related email notification for this thread.