Installed new hard drive, now Windows won't read SD Cards

Hi everybody, I've been having a problem I was hoping someone here could help me with.

I recently installed a second hard drive in my rig and ever since then Windows will not recognize my SD cards when I plug them in through an external USB reader. Cards of all sizes 128mb, 2gb, and 4gb, SD and SDHC. I'm positive the cards and reader are perfectly functional as they have been used in another computer and other devices. The USB port is functional as well.

I was told there might be a drive letter designation conflict as my SD cards were usually labeled G: and then my second hard drive had the G: designation. I changed my second drive to H:, but no luck.

Running Windows XP SP3

Any help in this matter would be appreciated as its frustrating me to no end. Thanks!