Passport for Mac - Media is in use and can't be powered off

I just purchased a Passport Essential 500 gig 3.0 usb portable drive.  I formatted it for Mac using the quick format program found on this site, and I keep getting a message that the “Passport 0740 Media is in use and cannot be powered off (try quitting applications and trying again)”    Every time this pops up I have to click OK so that the backup will continue.  Anyone else have this problem and if so, any help?

If I try to use this drive with Time Machine, it will only back up about 5 Gigs and then stop.

BTW, I am using a 13" MBP OS X version 10.7.4,   2.4 Ghz Intel Core Duo, 8GB 1067 MHz DDR3 ram.  I also use MacKeeper but have had it turned off during the installation of this drive and during the backup

Any help would be greatly appreciated!

ps.  While writing this post, the drive just completely shut off and is not recognized in the finder:confounded:

Hi, be sure to avoid using any extension USB cables or USB hubs, connect the passport directly to the MAC and check if that helps.