That error code is very general. It could be failed authenication but then again it could be that it failed to get access to the files it was trying to copy or the destination it is trying to copy to.
Does your admin' account have a password (instead of no password)?
Are you able to open the files you're attempting to copy?
Are you trying to copy a Junction Point?
Did you try using the System account?
The admi account does have a password, which I've entered
Yes, I'm able to access the files I'm attempting to copy.
I don't know what a Junction Point is, so I don't know if I'm attempting to copy it or not.
No, I'm not using a System account.
The external hard drive is not formatted as NTFS, it is a FAT32. Actually, it just might be formatted with NTDS. I didn't do that initially, so I under why it is not formatted in NTFS? Anyway, I'll check the permissions on the folder.