runas login issue - caot find the drive specified

I use the command:

runas /user:doug cmd

And I see the error "The system caot find the drive specified".

Microsoft Windows [Version 6.1.7601]
Copyright (c) 2009 Microsoft Corporation.  All rights reserved.
The system caot find the drive specified.

Some part of the login is looking for a drive. I don't have any drives mapped. Any ideas where I can look to find where this drive is specified?