Old KB, it may be worth reviewing the MS link to see if it applies to your environment:
"Cause: While this appears to be caused by the VSE Email Scanner, examining a Windows Performance Recorder Trace of the node reveals excessive wait time being consumed by Microsoft MSO.DLL.
Solution: This issue is not caused by VSE 8.8. Microsoft has indicated that correcting the Autodiscover provisioning alleviates this problem. Autodiscover is the mechanism used by Outlook to find the appropriate Exchange server. If Autodiscover is incorrectly provisioned, it can cause Outlook functionality to be dramatically impacted."
Slow performance with Microsoft Outlook when the VirusScan Enterprise 8.8 Email Scanner is enabled Technical Articles ID: KB86832 Last Modified: 3/22/2016
We are in the same situation. We have rolled out VSE 8.8 patch 9 mid April and our users starts complaining about the same beaviour as yours about Outlook. Disabling VSE Outlook add-in also work for us.
We have notice that when Outlook freeze MFEVTPS.EXE is using more CPU and has soon has it goes down, Outlook get's unfreezed.
I don't thinks it is related to Autodiscover in our case since it has been working fine for years and we start having probleme only in the last few weeks.
Have you found someting else that permenetly solve this issue?
No at this point disabling the VSE outlook add-in has been our only solution.
We did a complet uninstall of VSE 8.8 and then reinstall VSE 8.8 with patch 9 again using ePO and the probleme was gone. We tried an upgrade to ENS 10.5 patch 1 and it also worked worked for us.
Dupit, can you try that on your side and tell me if it also worked for you.
Same issue here.
VSE 8.8 Patch 9
I just tried uninstalling VSE 8.8, rebooted then reinstalled VSE via EPO. However, it did not fix the problem. Still freezes Outlook when emails are delivered. Did you uninstall the agent as well or just VSE?
EDIT: Actually, newly imaged machines exhibit this behavior for us as well which load VSE 8.8 Patch 9 from scratch. That rules out the uninstall/reinstall in my case
I am opening a support case.
I realised that reinstalling was only woking because Outlook needed to be restart in order to load VSE add-in after a reinstall. So, reinstalling VSE is useless.
I have open an service request and the support told me it is the expected behavior. I have argue that it was worst with patch 9 but since it is by desinged, there is nothing they can do about it.
Finaly, we disable it and we only rely on our Mail server AV solution for now.
Ugh, great. I had found that article previously but was hoping there might be something that could be done since it mentions 2010 not 2016 and only patches 1-3.
I am seeing this same issue since installing Patch 9. We have had multiple users complain about Outlook freezing when receiving new mail.