What does this error message mean?

[dnanian]

Hi, Ingrid. The problem here is that the OS has left an entry in the special /Volumes folder that -- for some reason -- is generating an error when we try to look at it to determine whether we should copy it or not. (I'm guessing that it's your iDisk.)

To fix this, just reboot the system (you might need to do so twice). Once that's done, the system should clean this stuff up, and you'll be OK again.