Hi,
Make sure you check the connection of the secondary drive. Make sure that the cables a properly seated on the connectors. Also check that you have the jumper settings on the drive correct (if it is on its own cable, try setting the jumper as the Master drive). Check that the drive has power by listening to it or feeling it when you start your pc.
If you still cant read the files system on the drive, run Recover My Files (from
Data Recovery Software to Undelete Files; Disk recovery; Recover Deleted Files) and first try a "Fast Format Recover" of the "physical" hard drive. If this does not work, then try a "Complete Format Recover" search.