so i compile my map and then this comes up when gmod tries to launch

there is nothing in the compile log about it, it something to do with gmod not launching right.
it only happens when i launch gmod through a map compile.

dont suppose anyone has found a fix for this?

I assume the easiest fix would be to start Gmod normally without ticking the “launch after compile” box?

Make sure steam is running when you are compiling the map. Hammer will try and lauch GMod through Steam once the map is compilied, if you aren’t logged on, it can’t check if you own the game, so it will throw that error instead.

its not that much of a problem. it doesnt affect the map compile so i will just have to get used to running the map manually

Are you running Hammer through Source SDK or “<game folder>/bin/hammer.exe”

cause Source SDK is dead, deprecated, and broken

i use the hammer located in garrysmod bin folder. isnt that how everybody else does it?

That isn’t true however. Its fully working and in fact necessary if you are mapping for older source mods - for example smod.