Blackberry 8830 - Removable Disk Drive Letter

[Whitemtntn]

We use Blackberry Enterprise server 4.0 and Desktop Manager 4.2 SP2
When I connect the Blackberry 8830, it mounts the F: drive to a Removable Disk for its Media Card feature. Unforunately, we use the F drive as a network drive and have for years. The BB REPLACES the network F drive, disconnecting my users from the network files. I have gone into Disk Management and reassigned the Removable Disk to X: This worked for a week, but now it seems to have decided to start using F: again for some users.
Does anyone know-- How can I FORCE the BB to use X: always and never use F:, or at the least, never override the network drive assignment? Or, how can I prevent the BB from even trying to mount the removable disk. (I tried to turn off media card support in Options, but it still mounted the disk)

Thanks,
Jack

 

[jpaf]

Turn off mass storage mode

 

[Whitemtntn]

Thanks but already tried that - still mounts a drive.