Cant update/install gmod server?

Hello, whenever i try to install or update a gmod server today it doesnt work, it validates then says everything is OK without actually changing anything. I tried a new directory and it tells me the empty folder is up to date then closes.
Any chance anyone could help me with this?
Thanks,
Sneaky

Sounds like SteamCMD problem to me? What are you typing into the SteamCMD? ( what commands are you using? )

Comment removed

Thankd for the reply Rubat, I’m typing in:

steamcmd.exe +login anonymous force_install_dir C:\GMODSERVERS\surfhdv7test +app_update 4020

+quit

[editline]9th March 2015[/editline]

I am such a tool… I missed out a + didn’t I?
facepalm
sorry guys