Need help with source engine

[ATGOD]

Ok so i have been using the source SDK engine for things such as HL2 mods , CSS maps but lately it wouldent start up steam showed that "servers.."whatever
Yes my steam has the undead patch i tryed to download source GCF but still wont work
any sugestions?

P.S. i also tryed that engine thing

 

[Renegade89]

you need to be more descriptive on the problem how can you expect to get help when you don't provide enough info?