AOE on my windows machine is unable to detect games setup by my peers (Windows 7) on the same network (LAN) or on the internet.
Is there something I should be doing (patch, fix) to join others with Windows 7/Vista?
I can see you've tagged this AOE 2 - we play LAN games of AOE 2 in our office network successfully with a mixed environment of Windows 7/XP machines. We did notice some issues with the colours in AOE on Windows 7 that were related to a clash with the windows theme - you can see the solution for that at: http://social.answers.microsoft.com/Forums/en-US/vistagaming/thread/a1763d12-11e2-498f-9b23-122792b14f74
With the networking, the only issue we saw was that the Windows Firewall blocked outgoing/incoming connections by default and we had to add exclusion rules for it, by clicking 'Unblock' in the dialog that pops up when the game runs. You would need to 'Alt-tab' out of the game to hit 'Unblock'.
Edit: Also, I have seen success disabling extra networks (wireless, lan, hamachi) when you're trying to play. Sometimes, for whatever reason, an unused/enabled lan network keeps you from connecting with your wireless one. Hamachi is great if you're using it but should be disabled when you're not.
Game Ranger allows players to connect to certain games with multiplayer issues, such as AOE 2 and its expansion.
Here is a solution that works most of the time.
Step 1: Enable UPnP on your Router. Please look for a way to do this on your particular router software. Here is how you do it for a router with DDWrt software.
Step 2: Open "Services" and set "SSDP Discovery" to "automatic". For this press the windows key and enter services.msc and open the first entry.
Then search for "SSDP Discovery" double click it and set it to "automatic".
Step 3: Make sure you have the same Default Gateway.
We had also issues because some people had different Default Gateways. Open the network connection, select TCP IPv4 and make sure all entries except the IPs match.
Step 4: Play game with TCP IP (the one where you input an IP address)
This solution worked for 4 out of 5 computers in our LAN. We could not attach the last one though.