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Windows 10 Build 2004
Outlook crashes intermittently and generates the following Application Event Log error.
Event 1000, Application Error (11:06AM, 12/7/2020) Faulting application name: OUTLOOK.EXE, version: 16.0.13426.20308, time stamp: 0x5fc6ea9b Faulting module name: ucrtbase.dll, version: 10.0.19041.546, time stamp: 0x73123758 Exception code: 0xc0000409 Fault offset: 0x0009edbb Faulting process id: 0x41c0 Faulting application start time: 0x01d6ccaedccaa9fa Faulting application path: C:\Program Files (x86)\Microsoft Office\root\Office16\OUTLOOK.EXE Faulting module path: C:\WINDOWS\System32\ucrtbase.dll Report Id: f8791f7b-faf7-452a-8ff2-7268662a6db2 Faulting package full name: Faulting package-relative application ID:
I have run SFC /SCANNOW
I have completely uninstalled and reinstalled Microsoft Office 365
Here are the properties of the failing file:
Locked Question. This question was migrated from the Microsoft Support Community. You can vote on whether it's helpful, but you can't add comments or replies or follow the question.
I also have a case open with Microsoft on this issue. It turns out that even rebuilding the Windows 10 profile did not resolve the issue. Hopefully, if Microsoft gets enough of us having the same issue with the UCRTBASE.dll file they will assign some engineering time to look in to this deeper. I will also post back here if Microsoft manages to find a permanent solution to the problem.
In our company, all workstations are identical (as well as the hardware, as installed programs) and all computers have SSD.
About 10 of 14 users are dealing with this issue.
At the moment I'm one of the lucky 4 who is not expierencing this problem.
Today I will test if the issue is computer specific or user specific by switching PC's and users.
Same issues seen here as well, we have maybe 8 users out of 15 that have the issue. All on latest Windows and Outlook. Most are using older machines with HDD, but there are a couple that have had a few crashes with SSD. Rest of the company not really affected and have SSD.
Also have open ticket with Microsoft but slow going with the usual bits they ask us to try gettign in the way.
From looking around the internet, there are various other programs with issues in the last few months and the UCRTBASE.dll file. I can see it was modified on several of our machines in December which conincided with some patches being applied, but not clear which one changed it.
Crashes outlook mainly when replying to emails, but some have had crashes with outlook just idling.
Same as other posts, the usual troubleshooting mentioned has been done.
Thanks for your reply.
If I make any progress, or get any insights in the problem, I will communicate it on this item as well.
The only consistency we've been able to nail down is that the faulting module is always that DLL, which is a software component of Microsoft Visual C++. The rest has truly been a head scratcher because it only affects a subset of our users, Office and Windows versions seemingly do not matter, and we have honestly tried just about every Google solution out there:
We finally bit the bullet and reached out to Microsoft and are actively working with them. Depending on the results there, I will make sure to update everyone here and all of the other message boards I've posted on.
Thank you.
