outlook 2019 crashes when opening calendar

NET Framework versions 4.8 and 3.5 which is why we’re seeing this behaviour. In this case, we’re running Windows 10 Enterprise 1909, Microsoft 365 Apps release 2004 on Semi-Annual Enterprise channel and devices Hybrid Azure AD joined, with the Microsoft MDM Security Baseline being applied from Endpoint Manager (formerly Intune) which includes an Exploit Guard policy. This often occurs when Windows is running the Microsoft. This happens because Windows Defender Exploit protection prevents Outlook from growing beyond its assigned memory. I came across this article from Microsoft which pointed to Windows Defender Exploit Guard:

NET Runtime version 7.9151 - Fatal Execution Engine Error (00007FFAAD0A6D4E) (80131506) NET Framework 2.0 runtime error when the crash would occur. I had an interesting issue at a customer recently where Outlook would crash to the desktop without error whenever a Teams meeting invite was selected – not ideal when we’re all trying to work from home!Įxamining the Application log in Event Viewer showed the following.

Outlook 2019 crashes when opening calendar