Unable to open shares on server

Unable to open shares on server - insufficient system resources

I was notified by some end users that they were unable to access shares on a server, they were getting insufficient system resources. I logged onto the server and got the same error trying to access the server’s own shares.

This error was in the event log

“An I/O operation initiated by the Registry failed irrecoverably. The Registry could not read in, or write out, or flush, one of the files that contain the system’s image of the Registry.”

Rebooting the box fixed the issue but here is the weird part. I did a proper reboot of the system but when it came back up it asked me to specify why the server shut down unexpectedly.