[Andrew]

uelia, I take it that other files copy correctly? I'm not very familiar with the Thecus NAS, but the "username:password" portion of the destination path looks suspicious to me. I don't know the mount options, but are you sure that the network mount is correct? If you're using Samba/CIFS, can you try AFP instead?

Alternatively, the symptom doesn't really seem to indicate this, but since the .ofocus file is actually a folder containing multiple files, one possibility is that the problem is with the name of one of the constituent files.

Once you renamed the .ofocus file, causing Finder to reveal it as a folder, did you try to copy that folder to your server? If the problem has to do with one (or more) of the constituent files, I would expect Finder to succeed with copying some files, then get stuck with the problem file, and give you an error message that includes the name of the problem file. That name might be enough to determine the problem.