I keep getting this error?

So, this is my first time trying to map, and I keep getting this silly error all the time!
I followed http://forum.facepunch.com/showthread.php?t=1212675 just like suppose to.
Heres the error:

I’d be so happy if you could help! Thanks in advance,

Try refreshing SDK content and reset game configurations


Also, you don’t need to do put Hammer in Garry’s Mod like that. You can easily create Garry’s Mod maps by mapping in Half Life 2 or CS:S format, then placing the .bsp into your maps folder.