This server could not be located on the network. This might be due to one or several of these reasons: a) The target server ...

This server could not be located on the network. This might be due to one or several of these reasons:
a) The target server is temporarily down;
b) There is a problem with the target server. Try running nettest and dcdiag on the target server.
c) The target server's DNS name is registered incorrectly in the directory service.