Robocopy Error 123

My Robocopy utility has been working fine for months and now it has stopped function. I am copying source W2K3 server to W2K8 server many times and it works, now it doesn't:

ERROR 123 (0x0000007B) scanning source directory y:\ebmsdocs\

THe filename, directory name or volume label syntax is incorrect.

Both servers are running fine and I can logon and RPC into them.

Any Ideas?

Kyle