Windows 7 - Weird problem with external HDD showing up but...

My old system was a custom built system but it was riddled with problems.

I had 2 HDDs on it, the first being the C: drive where the Windows XP OS was installed on it. The other drive was a seagate barracuda 7200.10 sata st3320620as

That PC crashed and I went out and bought a new HP PC with Windows 7 Personal 64-bit on it.

So, I took that 2nd Seagate Sata HDD out of the old PC and bought an external HDD case enclosure made by HornetTek and connected it to the USB port on my NEW PC w/ Windows 7.

The weird part is that it says it installed successfully and under Devices it shows up as USB to Serial-ATA Bridge

Under Disk Management it doesn't show up at the top but it shows up at the bottom saying the drive letter is F: and it's Removable Media

Regardless of all this, I CANNOT access the drive in any way whether I click it on Devices or try to go to F:\

How come I can't access it and how come it doesn't pop up as a HDD??? The data on it is VERY important to me and there shouldn't be anything wrong with the data on it. I just want to be able to access that data and for the HDD to be visible

Did the enclosure come with an adaptor? I'd download the Ubuntu live cd and see if I can take the data off with that seeing as its important, then stick the drive back in and reformat it. It can be used for backup.