I'm posting this because it took me hours to research the different fixes and I foudn one that's worked for me, and all of the people using my server so far. CLIENT SIDE: just because you used the Center map before, doesnt mean it works now, the Center map has been removed from the Workshop, but that does not remove it from your computer or subscriptions! Step 1 - UNSUBSCRIBE! - go to the workshop for ARK and browse subscriptions, find The Center (it will not work if you search for it) and click the unsubscribe button Step 2 - Right click on ARK Survival Evolved! and select properties - go to the 'Local Files' Tab and select 'Browse local files'. Then go to ShooterGame>Content>Mods and find the folder labeled 614734500 - DELETE THIS FOLDER Step 3 - restart your steam. I restarted my computer just to be safe, but others reported restarting steam worked for them. Step 4 - go to the Steam store and download the ARK DLC that is the Free Center Map addon. NOTE: when clicking the download button it does seem to start the ark game, but also started the download of the content at the same time (shows as a 1.1GB update download) - LEAVE THE GAME RUNNING WHILE DOWNLOADING. I'm not sure if its necassary, but some have reported that closing the client while the download was going on stoped the download. you should now be able to restart the client and start playing the game with the new map. Keep in mind, official servers for this map will not be up for a few hours yet. SERVER SIDE: Same as the CLIENT SIDE - just because you have the mod installed doesnt mean it will work. Depending on the type of server/provider you are uding, you may need to do the same steps as above (delete the content, then update the server files afterwards.) For myself, I use Survivalservers.com who has not yet updated the control panel to allow for the new map to be selected, but they have the files updated. Step 1: make sure the client is up to date - 241.1 should be what it reads, if you see anything lower, update the server. Step 2: change your launch parameters - for mine I left everything the saem EXCEPT the beginning part right before the "Multihome=", so my launch perameters look like this: /Game/Mods/TheCenter/TheCenter?Multihome=[the rest of the normal startup stuff] or TheCenter?Multihome=[the rest of the normal startup stuff] Restart the server, and connect - its worked so far! Best wishes!