Help can't share of see each other on the network!

[hockey man]

O.k. my bro came home from college and he and I are trying to connect our pcs so we can share files and play games against each other. However our netwok is now offcially "messed up" :( .

Here are some info on the situation:

Os: xp and 2000pro

He can ping me but I can't ping him. it says the request timed out.

He can't see me at all, but I can see him however I'am unable to do anything else. He can't see the other pc either, but my bro has the internet.

So any tips on how to get connected?

[PrntRhd]

Do you have a router?

[PrntRhd]

Here is a good link to check out for networking:
http://www.practicallynetworked.com/howto/

You want to check:
Computers both have unique names under 8 characters
Computers are both on the same Workgroup name
Computers have the IP addresses for both PCs in the trusted zone for software firewall/connection enabled on the XP computer. On 2000Pro/XP computers go to Run, type cmd and enter, type IPCONFIG in the resulting black window and enter> should show you the IP address for that PC (do this for both PCs) and post that info back here. IPs should be the same except for the last octet, and gateway IP should be the same for both PCs.
Users are on both PCs
Both Computers have at least one file that is shared and the 2 users have to have been given access rights for those files.

[hockey man]

We have a firewall router that the internet comes in on. the pcs are all plugged to that.

About workgroups, we stared a new one and my pc shows were both on it, but I can't get onto my bros and he can't see me. Could this be that his pc is set to not allow sharing? If so how do we change those settings on a 2000pro machine?

O.k. did the cmd thing.

Our ips [xxx.xxx.x.xx] are the same except for the second to last # his is .81 mine .31.
Subnet masks and default gateway are the same for both pcs.