How to block fake servers like Fastpath

If you're playing a Source engine game infected by these fake servers, your server list fills with spammed entries that end up putting you on a different server than the one you meant to join. At the time of writing, the Fastpath community is the primary abuser of this method.

You can still join other servers after landing on one of these — but because of the sheer number they spam, and their trick of using joining players to fake a high player count for a long time, it's easy to get pulled right back in.

One of the most important reasons to block these servers outright: joining them lets the operators use your Steam information to fuel their spamming method. They capture your Steam details, including the unique authentication used to join, and — unlike legitimate servers — they don't remove it when you leave. Instead your info and nickname get put on all their other fake servers for as long as it stays valid.

This pushes the fake servers high up the list and makes them hard to avoid, since they can spam as many as they want. On top of that they fake map names, server names (including names of servers you actually like), player counts, and even ping — though the ping is only faked in-game, not on the server list.