Stories, and bit rot, from the IT Support Trenches

or returned an unknown error.  You may need to reinstall the server application.”
The server application, source file, or item can't be found, or returned an unknown error.  You may need to reinstall the server application.

We had two cases of this error occur within a short time frame.

  1. “When I paste from Visio into Powerpoint, an error occurs.”
  2. “Clicking on a Visio diagram in a Powerpoint document, causes an error to occur.”

The solution was simple enough, and it was to re-register the Component Object Model provider, OLE32.dll.
regsvr32 c:\windows\system32\ole32.dll