Apply for the post-steampipe SDK beta (under TF2 properties in Steam) and launch hammer from...whatever folder hammer.exe is in (sourcesdk/bin/orangebox/bin? I don't know which version is used by SourceMP SDK).
Well I was about to post about this issue but saw it here. I hope valve figures it out soon. I was right in the middle of editing. I will just post what happened to me when trying to launch SDK for TF2.
When I try to launch Hammer I get a green box that says.
Warning
Configuration information for the game you're tying to edit is invalid or missing.
If I click Run Anyway I get a windows box that says.
Game infor.txt doesn't exist in subdirectory.
Check game parameter or Vconfig setting.
Look at all the other posts with tutorials. That quick fix doesn't seem to work anymore. Unless you use the GCF's, your out of luck 'til Valve gets on the ball.
This thread has not been updated in almost a month now. Also, in case you've haven't been looking at the other posts with tutorials, a new way to access Hammer has been released by Valve.
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