Location not available error while copying file from Server

I was copying a file from a Server to a PC when I got this error message below. Both network connection and the server were active and operational when I checked. I tried copying again after rebooting both PC and Server but I still got the same error.
Any advice on how to resolve the problem? Need your answer ASAP. And, thanks in advance.

Location is not available
C:User refers to a location that is unavailable. It could be on a hard drive on this computer, or on a network. Check to make sure that the disk is properly inserted, or that you are connected to the Internet or your network, and then try again. If it still cannot be located, the information might have been moved to a different location.
