Acrobat 9 Pro not recognizing mapped drives

I have a workstation in an enterprise environment that is having issues opening files from a network drive.  When the user tries to open the file directly from the network drive, Acrobat 9 Pro pops up a message that the file doesn't exist.  If we run Acrobat Pro, and try to open a file, the only drives listed are the local drives. The workstations are running Windows 7 Pro.  Other users running Acrobat 9 Pro on our network are not having the same issues. I have seen previous posts by people experiencing the same problem.  Has anyone come up with a fix?