The first thing to do would be to create an image of the drive so that any damage to or permanent loss of files during attempts to resolve the issue will not be the result.
The free Macrium Reflect is often recommended here:
http://www.macrium.com/default.asp
Do a 'File backup' rather than a Partition/Drive backup. This is so you don't carry any permission restrictions that might be attached to the drive/partition. If you are able to explore the image (after you create it), try copying files from the image to your desktop.
If you do have a backup of the files, check to see if you are able to copy or move them. If yes, reformat the drive in question and copy the backup(s) to it.
If no, and copying from the image doesn't work, then it's worth reiterating the Take Ownership method:
1) Back up your registry, saving the backup somewhere safe:
Registry - Backup and Restore
2) Unzip the downloaded file
3) Right click on the file, choose Merge
4) Log off and back on to the system
5) Right click on the problem drive and choose 'Take Ownership'.
Let it do its thing and try to copy the files again.
Worth saying again:
Do not apply this fix to your system drive or system files, junction points, etc. James