I am trying to network my desktop and laptop comuters using a crossover cable. Both computers are running Windows XP Home. So far, the two computers can see each other. I can ping one from the other. I can see shared folders. I can copy files from the desktop computer to the laptop. The problem is that I cannot copy files from the laptop to the desktop. That's not exactly true. I can copy small files -- say < 50 KB. I cannot copy larger files, such as 300 KB. The copy message box comes up but nothing more happens. Eventually it times out, and I usually get a message that say "specified network name is no longer valid". I've tired made sure that all firewalls and virus protection is turned off.

Any ideas on what to try next? Thanks in advance for you help.