Error when accessing networked XP machines.

[usalabs3]

I have 3 pc's networked using a router, I can access the other 2 machine from this machine that I'm writing this post with, but the pc in the bedroom, I can not access the shared folder on this machine, the bedroom machine can access the shared printer with no problem, but when my wife tries to access the shared folder on this machine, an error appears stating 'Insufficient server storage to process this command'.

All permissions are set correctly, the software firewall has been setup to allow access on port 139 on the network only, (internet access to port 139 is blocked).

Because I run web, file, chat, and email servers on this machine, I enabled the routers DMZ and only use the software firewall.

What can cause this error?

 

[usalabs3]

I found the problem, it was the IRPStack in the registry, I had to set it to 15, now, everything is ok.