Passport drive 'improperly ejected' when trying to run TM or use Disk Utility

I have a 320GB Passport drive, P/N WD3200ME-01, that I consistantly get  ‘disk improperly ejected’ error messages. I get the error when trying to run Time Machine and have gotten it when trying to use Disk Utility to analyze/repair the disk.

I an running Lion now (10.7.3) but also had the same/similar error with Snow Leopard. I don’t recall getting the error with Leopard, but don’t know if that just means the disk wasn’t failing then, or something changed in the Mac OSX after Leopard.  I have managed to get one good complete TM back up with the current Lion OS, so I’m suspecting something with the drive. The drive was not a dedicated ‘for Mac’ drive when I bought (Circuit City close out when they were going out of business) but I have formated it for the Mac extended (journaled) format. 

Thoughts? I’ve read some online reports of chronic port (mini USB driver and/or HW?) errors with the Passport drives.

Try downloading the Turbo Drivers

if that does not help you will need a power booster cable