Excel or Word Crashes on Open: Add-ins, Safe Mode and Repair

The user double-clicks Excel, the splash screen appears, and it closes. Or Word opens and dies the moment a document loads. There is no useful error, just a crash and an Event Viewer entry naming a DLL. The application is usually fine. Something loaded with it is not.

Nine times out of ten the culprit is an add-in, a corrupt Normal template, a broken printer driver, or a half-applied update. Safe mode tells you which in under a minute, so start there before you reinstall anything.

Start in safe mode and read the crash

Office safe mode starts the app with no add-ins, no custom templates and default settings. If the app runs fine in safe mode, the crash is caused by something you can disable. If it crashes in safe mode too, the install itself or a system component is at fault.

Read the crash entry before you change anything. The Faulting module name in Event Viewer often points straight at the offending add-in DLL or at a printer driver.

Hold Ctrl while clicking the Excel or Word icon, or run `excel.exe /safe` or `winword.exe /safe` from the Run box.
Open a document. If it works, move to the add-ins section below.
Open Event Viewer, Windows Logs > Application, and find Event ID 1000 from Application Error with EXCEL.EXE or WINWORD.EXE as the faulting application. Note the Faulting module name.
If the module is a third-party DLL, that vendor's add-in is your target. If it is a printer DLL, go to the printer section. If it is mso.dll or the app itself, run a repair.

excel.exe /safe
winword.exe /safe
Get-WinEvent -LogName Application -MaxEvents 50 | Where-Object { $_.Id -eq 1000 } | Format-List TimeCreated, Message

Isolate the add-in

Add-ins load from three places: COM add-ins registered in the registry, Excel add-ins (.xlam) listed in options, and files sitting in the XLSTART or Word STARTUP folders. Disable them all, then re-enable one at a time until the crash comes back.

Common offenders are PDF tools, older accounting connectors, document management clients and anything that has not been updated since the last Office feature release. Once you find it, update it or remove it. Do not leave it disabled quietly; the user will re-enable it from a prompt and the ticket comes back.

While in safe mode, go to File > Options > Add-ins. At the bottom, set Manage to COM Add-ins and click Go. Untick everything and click OK.
Repeat with Manage set to Excel Add-ins (or Templates in Word) and untick those.
Check the startup folders and move anything there to the desktop: `%APPDATA%\Microsoft\Excel\XLSTART` and `%APPDATA%\Microsoft\Word\STARTUP`. Also check `C:\Program Files\Microsoft Office\root\Office16\XLSTART`.
Close and reopen normally. If it works, re-enable one add-in at a time, restarting between each.
Check File > Options > Add-ins > Manage > Disabled Items. Office parks add-ins there after a crash and they will not load until you remove them from the list.

reg query "HKCU\Software\Microsoft\Office\Excel\Addins"
reg query "HKLM\Software\Microsoft\Office\Excel\Addins"

Clear the template and the cache

Word stores its defaults in Normal.dotm. Excel keeps a personal macro workbook and a cache of recent settings. Both can be damaged by a crash and then cause the next one. Renaming them is safe; the app rebuilds a clean copy on the next start and the user loses only custom defaults such as a preferred font.

For Word, close the app, rename `%APPDATA%\Microsoft\Templates\Normal.dotm` to Normal.old and reopen. For Excel, rename PERSONAL.XLSB in the XLSTART folder if it exists. Also clear the Office document cache under `%LOCALAPPDATA%\Microsoft\Office\16.0\OfficeFileCache`, which is where a broken cloud sync state lives.

ren "%APPDATA%\Microsoft\Templates\Normal.dotm" Normal.old
ren "%APPDATA%\Microsoft\Excel\XLSTART\PERSONAL.XLSB" PERSONAL.old

Printer drivers and Office repair

Word and Excel query the default printer when they open a document to lay out the page. A dead or corrupt printer driver, or a default printer on a server that no longer exists, can crash the app on open. Switch the default printer to Microsoft Print to PDF and try again. If the crash stops, remove and reinstall the real printer, preferably with a current driver from the manufacturer rather than the one Windows Update offered.

If safe mode also crashes, repair the install. Go to Settings > Apps > Installed apps, find Microsoft 365, choose Modify and pick Quick Repair. If that does not help, run Online Repair, which reinstalls Office in place and takes longer. As a last resort, remove Office with the Microsoft Support and Recovery Assistant and reinstall from portal.office.com. Check Windows Update as well; a pending .NET or Visual C++ runtime update sometimes leaves Office half-broken until the reboot.

Get-Printer | Select-Object Name, Default, DriverName
Set-Printer -Name "Microsoft Print to PDF"  # then set default in Settings > Printers

Frequently asked questions

Only one file crashes Excel. What does that mean?

The file is damaged, not the app. Open Excel first, use File > Open, click the arrow on the Open button and choose Open and Repair. If that fails, copy the sheets into a new workbook one at a time.

Office works in safe mode but I cannot find the add-in.

Check Disabled Items and the XLSTART or STARTUP folders. Also look at HKLM add-in keys, since add-ins installed for all users do not appear in the user's own options until they load.

Should I just reinstall Office?

Not first. A reinstall takes 20 minutes and does not remove third-party add-ins or the user's Normal template, so the crash often survives it. Safe mode and the event log get you to the cause faster.

Takeaway

A crashing Office app is almost always something it loaded, not the app itself. Safe mode splits the problem in half in seconds. Read the faulting module, disable add-ins, reset the template, check the default printer, and only then run a repair. Fix the root cause so the user does not re-enable the same broken add-in next week.