Event ID 8193 Volume Shadow Copy Service Error
Volume Shadow Copy Service error: Unexpected error calling routine RegOpenKeyExW(-2147483646,SYSTEM\CurrentControlSet\Services\VSS\Diag,...). hr = 0x80070005, Access is denied.
Context:
Writer Class Id: {0ff1ce14-0201-0000-0000-000000000000}
Writer Name: OSearch14 VSS Writer
Writer Instance ID: {07c936a8-347c-4e39-8014-2a057f611382}
Solution:
Go to the details tab within the event.
There you'll see some information AND a USER --> the SharePoint Search Admin Account.
Just give that user Full Control at the Registry Key:
HKLM\SYSTEM\CurrentControlSet\Services\VSS\Diag
After a Serverreboot the errormessage shouldn't appear again.