It can be slightly complicated depending on how lucky you are. The good news is there are a lot of people out there who have gone through the painful process and are willing to talk you through each step you have to do. OK, you have TS12. thats a good start and you have registered it. thats the 2nd step completed. Not that hard is it? lol. On the launchpad the build number should be 49922. Finally you should have a FST. (First class ticket). Now the sessions you should be looking to join will have to be downloaded. First ,mine is Port Ogden TS12 MP v1b. I,m not hosting at the moment I,m in Montana Rail Link. The two sessions you should download are UMR 2013 SUMMER MULTIPLAYER SESSION ver 2.4 by Lewis and Montana Rail Link 12 MP SEssion v2.3. These are the "must have" sessions. Dragging the session to the download box is all you need do as the route should be added automatically. I,m in Montana Rail Link at the moment as Jib is running a week long session so that would be a good place to start. UMR Summer is my favourite and is a 24/7 session and over a 24 hour period is the most popular session. Both are huge maps with Interactive industries although UMR has far more. They are both "end to end" routes unlike mine which is basically circular, and it will take you in the region of 3 hours or more to drive from end to end at line speed. But that,s enough of that. You must get in the session first. When you have downloaded the session You will probably find Montana has missing dependencies and possibly UMR as well. Your best bet is to try and join the session. If you can,t in CM select the route and click on it and select "Find dependencies". If there are any missing simply click on the tab at the bottom "view in content manager" or something. Then scroll down and drag all missing dependencies to the download helper. When finished recheck for missing dependencies. Then do the same with the session. If you still can,t join do an extended data base repair. And if you still can,t join you probably have locally modified assets. More of that later if the worse comes to the worst but easily fixed. I almost forgot. You need Teamspeak 3 for UMR SUMMER and Montana Rail Link but different channels. I have a chat room for my session in the UMR session. One final thought. All 3 sessions mentioned have threads on the first page of this forum to keep you up to date with events as they unfold. I could add a lot more but this is enough to get you started. If you want to talk to me directly I,ll be in the Montana TS Channel. Montana Teamspeak is 108.91.138.12 and UMR is 66.45.231.18