Windows 10: MS Excel 365 sometimes won't start

Hi there, @skcusime.

I've been using Office since 2000 Pro, so have a little experience at it. Every now and then certain machines have problems either caused by OS or Office update. Sometimes difficult to find which. In your case it looks like the FCU update botched Office. It's usually the Click-to-Run Extensibility Component that can't change certain protected system Registry keys. I see it ran in your Reliability list. It'll most likely be an Office update that will fix the problem.

The "magic 8" times open/fail is a mystery to me. Never saw that one before. Interesting.

A few questions if you want to continue:

Does this happen with other Office programs or just Excel?

By any chance have you changed from 32 bit to 64 bit at any time?

Does opening just the Office program by itself quicker than opening a file?

I see you uninstalled/reinstalled. Have you tried the repair option? Settings app > Apps > Left click MS Office > Modify > Yes to UAC > Online repair. If that doesn't fix it, most likely nothing will. However, there is a way to uninstall that component for a time, but I don't recommend that.

BTW, uninstalling/reinstalling sometimes causes more problems than helps. It causes Registry key problems. I recommend always using the repair option and reboot.

There's been a new problem that has arisen that they need to fix. Not all systems, but, believe it or not, Cortana causes issues. Just for grins try turning it off if you have it enabled. Settings app > Cortana > Talk to Cortana > Turn off "Let Cortana respond to "Hey Cortana" > Reboot.

 

Hello HippsieGypsie,
It only happens with Excel, although I usually only use Excel, Outlook & Word. I have tried all the others in the Office package, just to see, and they all worked, but so does Excel most of the time.
I use a 64 bit version of Windows, but a 32 bit version of Office. No changes.
I've done the quick repair and the long online repair, which seems like a re-install with the need to re-sign in at the end.
I've never used Cortana and it's turned off.
It now about 7am, and i left the computer on all night (it's usually off) and have had no problems this morning so far. Excel is usually one of the first programs run each day, and of late i'm careful to make sure it's had time to finish it's bootup before trying anything.
Yesterday, after a reboot, I tried running it in safe mode but it happened then too. So that eliminates any addins (i don't have any) but it seems the first run after a boot is the most likely to fail.

 

Ok, skcusime. Hopefully they release something soon. Good luck to you. *Smile

 

I've spent the morning trying different scenarios.
It seems to happen consistently on the first run following a startup or reboot (i hadn't pinpointed that before). After that, subsequent runs, either from the start menu or opening a workbook excel opens okay.
I've tried a registry change as per https://support.microsoft.com/en-us/...r-cannot-start - didn't make any difference.
I've tried running in safe mode and running as administrator - both failed.
I've disabled hardware acceleration - didn't work.
All other Office programs work as they should.





So today I've rebooted 5 times and I'm now up to 40 errors - exactly 8 times for each try. Consistent - happens on first run after a boot and happens exactly 8 times!

 

Well, way too early to be 100% sure, but it appears this whole saga was caused by Malwarebytes. I turned it off yesterday and Excel worked after a boot without problems, and loaded very quickly. I've now turned Malwarebytes on again, but set an exception for Excel. It appears to be working - so far so good.

 

That's great news. Who'd of thought. Hopefully that does it for you. Good luck. *Smile