I have a 1.5TB external HDD formatted with NTFS (I think) with one folder containing approx. 600GB worth of data. I had temporarily switch to PC-BSD a while back (until I fried the drive it was installed on), and the GB folder was readable, even though it was no longer readable on some other computers. Now I'm back to Ubuntu, and none of my Ubuntu systems can read the folder. I can't change permissions even as 'sudo'. All the other folders on the drive have the same permissions set, but the one folder gets the following error when I try to list the contents:

ls: reading directory .: Input/output error

I can't get more info. All my scans show no directory/file structure errors.
I really need this data and I'm out of ideas.
Any suggestions where to start?

It may be time for you to read a bit about testdisk:

http://www.cgsecurity.org/wiki/TestDisk

Sounds like you need to fix the partition. You may try ntfsfix in linux, or boot in Windows and use chkdsk.

If you don't use windows you should, after recovering your data, reformat the drive to a linux filesystem.

Brian

Did you boot into Windows???

I'm going backpacking in the mountains first thing tomorrow, so I'll look into your suggestions when I get back. Thanks for the quick answers.

biggie_ I didn't boot into windows (don't currently have a working copy...just one very screwed up copy that won't boot). Last time my roommate tried using it with his netbook I don't think he could see the contents of the drive if I remember correctly. I'll try his computer when I get back too.