I am running Ubuntu 12.04 and I have a 500GB external hard drive, formatted in ext4, which I have used for about a year to store batches of data that I am sifting through. About once a week I move a chunk of data from the external drive to my internal drive for processing. As I do that I delete the data from the external drive and empty the trash, thereby clearing up space on the external and also preventing myself from grabbing stuff that I've already sorted through. The vast majority of this is text files, but there are a few .jpegs and .mp4s thrown in, if that matters. Anyway, this has been working without a hitch for nearly a year.

So today I plug in the drive and I have an odd issue. I was able to move folders from the external over to my internal drive with no problem, but when I tried to delete those files I was unable to do so. I kept getting the "unable to send file to trash, do you wish to delete permanently?" message. I clicked yes / delete all, but no files were actually deleted. It just sat there. Even worse, while the system was trying in vain to delete those files I was unable to move more files over. In short, I was stuck.

I canceled the operation, unmounted and remounted the drive, and then I had an even bigger problem. I have a spreadsheet of all the different folders on there ( exactly 818 ) and yet when I opened the drive in Nautilus, it was only finding 512 folders. So I had 306 missing folders, but my free space was unchanged.

Immediately I think that the drive may be corrupted. I went into Disk Utility and ran the check disk option. It said that the drive was NOT clean, but offered no remedy or option to repair. I went back into the drive in Nautilus and once again attempted to delete the files I had already moved. Same issue. I clicked on Details and it said that it was unable to create a trashing file I/O error. I've looked, and it's not a permissions issue. The drive and all folders that are in it all belong to me, and they are all read / write. I've started running badblocks on the drive, but it looks like that is going to take several hours to complete. Any ideas?