Plugin update freeze that only continues after Windows Server reboot
Please install the fix below from Microsoft to resolve the issue.
Here is a list of patches for that issue per OS version:
2008 SP2: https://support.microsoft.com/en-us/help/4345397/improvements-and-fixes-for-windows-server-2008-service-pack-2
2012 Non-R2 is here: https://support.microsoft.com/en-us/help/4345425/improvements-and-fixes-windows-server-2012
2016: https://support.microsoft.com/en-us/help/4345418/july162018kb4345418osbuild143932368
You might run into this after the server reboot.