|doesn't sound like routine server maintenance has been performed regularly.|
you changed dns to what? it should be pointing to itself
your workstation dns, is that set to the ip of the server?
I would suggest you get back in under safe mode.
run chkdsk /r on the drives
run disk cleanup with everything checked
check the event viewer logs for errors
Answers are only as good as the information you provide.
How to properly post a question:
Sorry no tech support via PM's