I administer an Intranet Server but I am facing a problem since
returning from leave. Apparently, someone run an easy registry cleaner
tool to remove certain registry keys. I found out again that the server
was attacked by a virus(Backdoor)and was healed by the antivirus.
Now, users are able to logon to access files witin a maximum of 20
mins. After that the get the error, "An error occurred while
reconnecting to the drive. The specified server cannot perform the
requested operation. The connection has not been restored."
Yet the server is on and functioning.

What can be the cause?

Thank You.