Windows 7 cannot read my external

So I just upgraded to Windows 7 home premium on my Compaq Presario F700 this evening. All was going great until it was time to start transferring files back over to my laptop. The first files I transferred were setup files for various programs and not in a folder on my external hard drive (Seagate 500gig in Metal Gear Box enclosure). Those files transferred without any problem however, when I went to open one of my folders on the drive, it said that the folder was empty and that it needed to be formatted. The hard drive and folder worked fine when I was running vista. My other external hard drive (Seagate 320 gig in Metal gear box enclosure) works fine. Both drives say they are NTFS file systems. Also when I look at my computer, it says that over 140 gigs of space is used.

Can anyone help?

I have that randomly with my external hard drive as well. Says it needs to be formatted. Which obviously is not the case. Try rebooting your computer and plugging the external drive into another usb port. Try also rebooting your external drive. Good luck!

Snarks

I have the same problem. Sometimes it can read it, sometimes it can't.

Yea, thats exactly what's happening... I've tried rebooting both my comp. and the external. I've tried using a different usb port but alas, the problem exists. I'm going to try to see if it will work on a different computer tomorrow and I really hope it does because if not, I just lost 140 gigs of extremely important data...

Thanks for your suggestions though!

Yeah, I just booted into XP and my external is working just fine.

Well, for mine, it shows up with a drive letter just fine. Most of the time it just says access denied when I try to go into it. Sometimes it works. Sometimes it works for a while then says access denied a little bit later. As for the USB power issue:

1. Why would it be an issue in Windows 7 but not XP?
2. How could I verify if that is the problem?
3. What should I do about it if there is a USB power issue?

Ah...good call. I knew I forgot something.