RDP Web Connection: drive redirect fails

Archived from groups: microsoft.public.windowsxp.work_remotely (More info?)

I am running the remote desktop web connection client (5,2,3790,0) against XP
workstations. Disk redirect is enabled. My clients are XP and 2000.

Occasionally, drive redirect fails. This is always for the C drive on the
client (\\tsclient\c). The drive does not appear in the list, and trying to
browse to \\tsclient\c gives an error (network name not found or something
like that). When this error occurs, all clients seem to have the same
problem. Other drives on the client, such as A, D and network drives, work
fine. It is only the C drive that is causing problems.

An interesting observation is that if I try to connect using the standard
Remote Desktop client, drive mapping is reestablished. After this, the web
client also works. After some time, however, the problem reappears.

We are dependent on using the web client. Has anyone run into this issue
before or have any recommendations for further investigations?

Thanks in advance.