Downgrade to play with friends

01Why you can't connect

Most multiplayer games — co-op survival, Source titles, the whole genre of "play with your friends" games — only let matching versions talk to each other. The moment a patch ships, a group fragments: whoever auto-updated is on the new build, whoever didn't is on the old one, and a dedicated server sits on whatever version its host last applied. The error wears different clothes per game ("version mismatch", "incompatible", "wrong build", or just a server that won't appear in your list), but it's one cause: the versions differ. No setting fixes a mismatch from your side alone; the only fix is everyone landing on the same number.

02The rule: one version, everyone

There are only two ways out of a mismatch, and both end with everyone on one build:

• All update. The simplest, when it's available — everyone takes the patch and the group is current again. Do this first if nothing's stopping it.
• All downgrade. When updating isn't an option — a mod the group depends on hasn't caught up, the new patch broke something, or a server is deliberately pinned — everyone rolls back to the build that works instead. That's where this page and DepotDownloader come in.

The discipline is short: pick the target version, and make sure everyone — every player, and the server if there is one — is on it, mods included. A group half-matched is a group that can't play.

03Pick the target build

Decide which version everyone matches to:

• Joining a server? The target is whatever version the server runs — match it exactly. Many community servers stay on a specific patch on purpose; the server's info or its community will tell you the build.
• Just playing with friends? The target is the last build everyone's setup actually worked on — usually the version before the patch that broke things, or the one your shared mod list supports.

Then find that version's manifest on SteamDB (the find-your-IDs guide covers it) so everyone downloads the same build, not "roughly that era." Version matching is exact — close isn't connected.

04Get everyone there

Each person who needs to roll back does the standard download — same App ID, same depot, same manifest:

Then everyone installs and pins it — set the game to "only update on launch" so nobody silently gets dragged forward and breaks the match again. If the game is modded, the group also needs the same mods at the same versions — a matched game build with mismatched mods often still won't connect; that's the downgrade-and-keep-mods discipline, applied across the whole group. Practical tip from every group that does this, and what bit my group until we made it a habit: name the exact version (and mod list) in the chat, so everyone confirms they're on it before you try to connect.

05Matching a server

If your group runs its own dedicated server, it's just another thing that must match — server and clients on the same version, full stop. The server's build is usually a separate free app you download anonymously, pinned by the same manifest logic. Keeping a server on an old version on purpose (so a modded campaign or a stable patch survives) is a common, legitimate setup — the per-game guides for the big co-op titles cover the exact app IDs and quirks: Palworld, Valheim, Project Zomboid, 7 Days to Die and the Rust guides all show the server-plus-clients match for their game.

06The anti-cheat line

One honest boundary. For games with no anti-cheat — most co-op survival titles — matching an old version among friends is completely ordinary, the use case the whole genre assumes. But for VAC-secured or anti-cheat games, an old client can't join official, secured servers: those run the current version and the anti-cheat expects it, so old-build multiplayer there is off the table by design. The legitimate space for an old version in those games is private servers, friend groups, and unsecured/community servers that don't enforce the current build — which is exactly where version-matched play belongs anyway. Keep matched old builds to your own circle and the connect-with-friends use case stays clean. If it were my group, I'd settle on a private or unsecured server up front and not even tempt the official-server line.