I've messed around with Hammer for a while now and recently stated a new TF2 map and decided to make it a KOTH game mode. Before I'd decided on the game mode I had a basic layout for the centre of the map and had compiled it without error numerous times. In terms of entities, it only contained info_player_teamspawn info_observer_point light_environment a few light_spots a few info_overlays and a few prop_statics I then tried to add a KOTH point following a few different walkthroughs. I'd seen conflicting advice on whether to add a tf_gamerules entity but I decided to add one to make the various outputs work. After I'd set up the KOTH point I compiled the map in VBCT and as usual told it to run the map after it had done compiling. It complied fine, but when it came to running the map TF2 just hung on the main screen. After forcing TF2 to quit I tried opening it normally and testing the map by creating a server, but this also made the game hang. I then tried removing tf_gamerules and recompiling, but it still crashed. Even taking out all the KOTH point stuff didn't work. What's really odd is that now I can't create a server using any map, even the official ones, but luckily I can still join servers. I put my compile log through interlopers.net but it didn't turn up anything unexpected. I've posted it below for reference. Update 1: Changing the compile setting has no effect Update 2: Refreshing the SDK content and resetting the game configuration in the Source SDK has no effect. If anyone can help it would be greatly appreciated.