A family of Microsoft spreadsheet software with tools for analyzing, charting, and communicating data.
If this problem affects all Excel documents and are you using Office on a Windows device?
1
If you are using Office on a Windows device:
Press and hold Ctrl on your keyboard while you open Excel, does Word open correctly in Safe Mode.
If it does, try uninstalling any add-ons you may have installed in Excel.
If that does not resolve the problem, the best option is to perform a full online repair of your Office installation.
Open the Settings App (gear icon on your Start Menu).
Go to Apps - Installed, then scroll down to find Microsoft Office
Select that and choose Modify - Online Repair
That should fix any issues with your Office Installation.
2
If you are using Excel on an Apple Mac computer, please provide a screenshot of the error you see in Excel.