A family of Microsoft spreadsheet software with tools for analyzing, charting, and communicating data.
Run a full Online Repair of Microsoft 365 from Windows Settings rather than relying only on the Repair now button in the Excel error window.
Repair Microsoft 365
- Select Close on the Excel error message, then close any other Office applications.
- Open the repair settings:
- Windows 11: Right-click Start → Installed apps.
- Windows 10: Right-click Start → Apps and Features.
- Find Microsoft 365 or Microsoft Office.
- Select the three dots → Modify.
- If Excel was purchased as a standalone application, find Excel instead.
- For the usual Click-to-Run installation, select Online Repair → Repair.
- If the window instead shows an MSI installation, select Repair → Continue.
- Complete the prompts and restart the computer if requested.
- Start Excel by itself first, then open the spreadsheet.
Online Repair is the more complete option; Quick Repair only detects and replaces certain corrupted files. Repairing Microsoft 365 repairs the entire Office suite, even when only Excel is affected. ^1^
If Excel still produces the error
Test whether an add-in is preventing Excel from starting:
- Press Windows key + R.
- Enter:
excel /safe - Select OK.
- If Excel opens successfully in Safe Mode:
- Go to File → Options → Add-ins.
- At the bottom, choose COM Add-ins from Manage, then select Go.
- Clear all add-in checkboxes and select OK.
- Close Excel and start it normally.
- If normal startup now works, re-enable add-ins one at a time, restarting Excel after each one, to identify the conflicting add-in.
Safe Mode bypasses Excel add-ins, startup locations, and several customized settings, making it useful for isolating a startup conflict. ^2^
If Excel cannot start even in Safe Mode after Online Repair, note whether other Office applications such as Word also fail and whether the problem affects every workbook or only this particular spreadsheet; those details determine the next troubleshooting path.
References