Hammer not working

Garry's Mod mapping
#1

I open up SDK and (using hl2) click hammer, I get the egg timer next to the arrow mouse icon and then nothing happens

While using HL2 ep 2, no error message, basically, all the windows pop up for about 1-2 seconds, then it just closes.

I was using it yesterday, I have tried to reinstall it

#2

Try verifying game cache, refresh SDK content, reset game configs and if that doesn’t work, delete clientregistry.blob.

#3

Try opening up your Task Manager and closing out of the process.