Ok I have got some pretty good help from everyone on here so far so lets see if anyone can figure this one out. I have a WD Passport 320GB External Drive and it shows 298GB Available. Ok fine. Now it says I still have 185GB used and 112GB free. But here is the problem, I can not copy any more files to it because it has an error that says "Cannot copy *****.*** There is not enough disk space. Delete one or more file to free disk space, and then try again. To free up space on this drive by deleting old or unnecessary files, click Disk Cleanup." I can not figure out how I am out of disk space. I should have pleant enough to copy whatever I want to. Any help would be appreciated. Thanks.
IIRC, WD Passports have software that allow the owner to "write-protect" the drive. Maybe that's what happened? Can you also try the drive on another computer?
You can also check if there's really space left by going to Windows Disk Management (Windows+R, type "diskmgmt.msc", Press Enter).
Last resort is to see if you can back-up the drive, format it, and try again.
Well as for the write-protect, I have never set that and I use this drive on a daily basis. I back up all my movies, games, music, etc. I just never had it this full. Disk Management shows that there is 298.02GB Total and 112.71GB Free(37%). I am stumped. This makes no sense to me. I am going to contact WD today and see what they say. If you think of anything else, I will be open for any advice. Thanks.
Well, I figured it out I think. WD support told me that since the HD is FAT32 format, I can not copy files larger than 4.0GB in size. I have to backup and then format the drive to NTFS. It sound correct but I would like someone to verify that this is correct because I do not want to spend forever copying files for nothing. This is a lot of data to move around and is going to be very time consuming. Thanks.