Microsoft says that Outlook might take a minute to start and display the splash screen on devices running Windows 10, version 1809 or later if User Experience Virtualization (UE-V) is enabled.
This new issue was acknowledged by Microsoft in a Windows support document where the company details the exact scenario that could break Outlook’s startup functionality.
Only affects Outlook 2016 and 2019
As Microsoft says, the bug affects Outlook 2019 or Outlook 2016 users if they have installed any Windows 10 cumulative updates released after March 17, 2020.
For the issue to impact their devices, the Outlook users must also have deployed UE-V with the Sync Method set to None and a UE-V template registered such as MicrosoftOutlook2016CAWin32.xml.
If all the conditions above are met, Outlook will take one minute to start and display the splash screen on their devices.
The bug is caused by the UE-V Sync method being set to None which is causing Windows to ignore the default synchronize timeout of two seconds, leading to UE-V timing out after one full minute.
How to resolve the one-minute Outlook startup delay issue
To solve this problem and have Outlook launch without delay, Microsoft recommends switching the Sync method to the default SyncProvider.
“The Sync method None is specific to workstations that have a permanent network connection to the SettingsStoragePath,” Microsoft explains.
The other workaround requires customizing the UE-V template to change the behavior of UE-V itself by going through the following procedure:
- Go to the TemplateCatalog path that is defined in the UEV Configuration settings. If you use the default location, the path should be as follows:
- Update the following lines in the template, and then save and re-apply the new template:
Microsoft reminds also Outlook users to not edit the template for a version of Office other than Office 2019 or 2016 since it will potentially cause crashes and unexpected behavior.
Last week, Outlook users around the world were also experiencing crashes when starting the app, with 0xc0000005 errors being added to the Windows Event Viewer.
After tweeting that the crashes were being caused by a recent update, Microsoft released Outlook version 13001.20384 to fix the issue.