Exchange 2010 logs failing to truncate

[AlexLeadingEdge]

Case # 02378199

Exchange 2010 on VM of Server 2012 R2 on a Server 2012 R2 Hyper-V Host. Exchange logs failing to truncate. Listing VSS writers, the Exchange VSS Writer is missing. Based on the logs it has stopped over 3 weeks ago. No Windows Updates for 3 months.

[AlexLeadingEdge]

I may have figured it out. It looks like that since a Windows Update for a PREVIEW for .NET framework for July 2017 it has been blue screening every few days since the patch was installed with the error message REFERENCE_BY_POINTER. Microsoft Technet says that it is caused by drivers referencing to the kernel but not un-referencing (ending the resource call) afterwards, which then eventually causes an overflow within the kernel, which then ends up as a BSOD.

After the BSOD the Exchange VSS Writer doen't seem to start, but doing a restart normally does.

I have updated the .NET Framework to the latest FULL version and will monitor over the next month to see if this has fixed the issue.

I also note that there is an update to SQL Server 2016 Service Pack 1 Cumulative Update (CU) 5 KB4040714, which I will do if the server has another BSOD within the next 7 days.

[AlexLeadingEdge]

I see on the Hyper-V Host that when I list the VSS writers (vssadmin list writers) it is also saying that the "Microsoft Hyper-V VSS Writer" is in a "[8] Failed" state with a "Non-retryable error".

This lines up with the "Hyper-V Virtual Machine Management" service. What would happen if I restarted this service while all the VMs are running? Will it break any current operations? Will do it after 5pm and see what happens

[AlexLeadingEdge]

Restarting the service has fixed the VSS writer status, and nothing bad happened to the VMs (that I can see at least!)