Server join crash

Graphics Card: ATI Radeon HD 4600 Series
Processor: AMD Phenom II X4 925 Processor
OS: Windows 7 Home Premium
RAM: 4.00 GB

I can join my friends listening server, but when i try to join an RP server (“best serious rp”) it crashes after it hits the “sending client info” screen. behind the game, a box comes up saying HL2.exe has crashed. I have joined and joined and still no luck. please help!!

Try clearing out your addons and then try joining the RP server