Outlook: Temporary fix for crashes when writing mails

[German]Classic Outlook version 2412 (build 18324.20168) can crash when creating a new email or forwarding emails. Microsoft introduced a temporary fix on January 17, 2025 and plans to solve the problem with an update at the end of the month.

Crashes in version 2412 (Build 18324.20168)

On January 7, 2025, version 2412 (build 18324.20168) of the Microsoft 365 apps was released by Microsoft in the Current Channel (see here). This version already attracted attention due to crashes of Outlook and Excel under Windows Server 2016 (see my blog post Microsoft Outlook 365 or other MS 365 apps are dropping suddenly errors). Microsoft now claims to have corrected this crash bug (see Microsoft fixes crashing Microsoft 365 (Office) apps (16. Jan. 2025)).

But there is a second crash problem with the Outlook Classic client, which Microsoft confirmed on January 17, 2025 in the support article Classic Outlook crashes on reply and forward in Outlook for Microsoft 365, Outlook 2021, Outlook 2019 and Outlook 2016.

After updating to version 2412 (build 18324.20168), classic Outlook may crash when starting a new email or when replying to or forwarding an email.

Administrators can check if this issue is occurring by searching for crash event 1000 or event 1001 and the following event details in the Windows Event Viewer application log:

Name of the faulty application: OUTLOOK.EXE, 
version: 16.0.18324.20168, timestamp: 0x677828da
Name of the faulty module: OUTLOOK.EXE, 
version: 16.0.18324.20168, timestamp: 0x677828da
Exception code: 0xc0000005
Error offset: 0x0000000001a7c02a
Incorrect process ID: 0x0xFD0
Start time of the faulty application: : 0x0x1DB65D0FD0B9857
Path of the faulty application: C:\Programs\Microsoft Office\root\Office16\OUTLOOK.EXE
Incorrect module path: C:\Programs\Microsoft Office\Root\Office16\OUTLOOK.EXE

Microsoft states that the above issue has been resolved with Microsoft 365 version 2501 build 18429.20000. This build is scheduled to be rolled out in the Current Channel on January 28, 2024.

Microsoft proposes a workaround

Administrators whose users are affected by the crashes have the option of rolling back from Microsoft 365 to version 2411 (build 18227.20162) until the new version is rolled out. This requires the following procedure:

1. Open a Command Prompt in Administrator context.
2. Type or paste the two commands into the Command Prompt window and press Enter after each:
   
   cd %programfiles%\Common Files\Microsoft Shared\ClickToRun
   
   officec2rclient.exe /update user updatetoversion=16.0.18227.20162
3. To prevent Office updating back to the latest build you can turn off updates by selecting File > Office Account > Update Options > Disable Updates.
4. Put a reminder on your calendar for February 11th to re-enable updates. Or, check back on this Known Issue in case it is addressed sooner.

(via)