John:

To elaborate on what Mark replied, I had a similar problem. On my development machine, I had a drive mapping as a convenience to keep from having to change directories via UNC. I accidently added a table to the DBC which used the actual drive letter and path as the location. My intent was to add it using UNC. Because my users did not have this drive mapping, the DBC could not locate the table. I had to remove the drive mapping from my machine, use the table exclusively to remove the link, then add it back using UNC.