Transcend 8gb PendriveShows Me into 2 terabyte and drive is in unusable

I assume you have tried different USB ports.
If it's still occurring no matter what then, Format it to FAT32.

Is it new... or from a friend or what?

I used to run Win 95 on some old computers that I got from a school that was remodeling. These things were running like 800MB HD's (Once and a While I'd get a 2GB).

This is where I learned most of what I know about computers. Anyway... you could format a floppy disk (or the HD) in FAT and then use drivespace to make it massive. I'd get like 50MB free space on a standard 1.44MB floppy. You couldn't actually put that much on there. Anyway I was thinking that someone may have done that to your Pen Drive and most newer versions don't support drivespace anymore.

Just a Thought...

(BTW If it is actually 2TB you have an extremely valuable piece of hardware)