Cannot access new laptop

[ajmurray]

Okay, here is the scenario.
Have 3 laptops all running on XP pro.
The newest laptop,(AJM'slaptop) can ping to the other 2 laptops, respectively named:Mikeslaptop and IBM-Murray. Likewise, Mikeslaptop and IBM-Murray can ping to each other as well. In addition, I am able to print documents from any computer in the network as well as view all three computers in the network.

Here is what I cannot do:
Mikeslaptop and IBM-Murray cannot ping to AJMslaptop.
Mikeslaptop and IBM-Murray cannot access AJMslaptop without getting the error...AJMslaptop is not accessible. You may not have permissions to access...blah, blah.
I have tried many suggestions including removing the firewall and changing the register, you know, the whole registeranymoussam etc. but to no avail.

All and any help would be greatly appreciated.

[btdav]

The pinging thing would lead me to believe it is a cable issue. But since you can print from the computer I'm not sure.
The permission error I'm pretty sure has to do with user settings on AJMslaptop. I had the same error on one of my systems until I changed the user and group settings on the system that wouldn't access.
By the way, what versions of XP are on all three systems?

[ajmurray]

btdav,

The newest laptop (the one that can ping to everyone else, but cannot be pinged, is running Media Center Edition. The other two, the ones that can ping each other, but cannot ping the newest laptop are both running on XP Professional. Could that be the reason?

[btdav]

Sorry for the late reply. I was on vacation. Is the Media Center one running XP2? If so, check your port settings.