Steam – How to get Rainbow 6 Vegas 2 to work with multiplayer on Steam

As far as I know, you can't do that. If one of you wanted to play single player, then you could possibly set one computer to Offline Mode before starting the game, and then the other person should be able to log in on the other account and play multiplayer, but both of you being online at the same time should not be possible.

Keep in mind, this is technically not allowed. Steam's agreement says you're not allowed to share your account or your games, that includes your fiancee. I don't think they actually do anything about it as long as you're not talking about it on steam chat or their forums. However, you still risk losing your account and all your games when bypassing their rules.

EDIT: As of mid 2014, Steam has released Steam Family Sharing, which enables the sharing of Steam libraries. However, this system does not work on a per-title basis (only during the beta), but rather - If one title is being played, all other titles cannot be played (unless it's the same user that's using the library that is launching the second/whatever-is-after-first program).

Ubisoft has yet to provide a fix for this issue. All you can do is log in again and again until it works. As user juicyfart so eloquently puts it:

I have a new pc connect to internet no router, no nothing and this piece of crap doesn't work.

If you're still feeling determined, you can try forwarding the following list of ports. Ubisoft also insists that setting your computer as DMZ will let the game work. However, setting your Windows PC as a DMZ will expose it to attack over the internet (i.e. that's a very bad idea):

An easy way to make Rainbow Six Vegas 2 work behind your router is to setup your gaming PC as the DMZ. To learn about how to setup your gaming PC as the DMZ, check your router’s documentation.

If you don't want to set your gaming PC as the DMZ, then you'll have to do some special configuration to your router or firewall to make sure all the game’s features work properly.

Here are the ports you'll have to open, or forward.

Login/Matchmaking services: Outbound TCP 3074 (generally don't need any configuration for this)

Gameplay: Outbound UDP 3074-3174 (generally don't need any configuration for this) Inbound UDP 3074-3174 (on a firewall, you must allow inbound traffic on these ports, on a home router with NAT, must forward inbound traffic on these ports to your PC)

Custom Head: Outbound TCP 10130 (generally don't need any configuration for this) Inbound TCP 10130 (on a firewall, you must allow inbound traffic on this port, on a home router with NAT, must forward inbound traffic on this port to your PC)

10130 is the default port used by the Custom Head feature. You can change this port in the Extras\Options\Multiplayer menu.

Voice Chat: Outbound UDP 10140 (generally don't need any configuration for this) Inbound UDP 10140 (on a firewall, you must allow inbound traffic on this port, on a home router with NAT, must forward inbound traffic on this ports to your PC)

10140 is the default port used by the Voice Chat feature. You can change this port in the Extras\Options\Multiplayer menu.