Preparing to launch Garry's mod...

After the steam downtime, I noticed that I could no longer start up Garry’s mod, the window with “Preparing to launch Garry’s mod…” would appear and wouldn’t do proceed to launch the game, it would be stuck. I’ve already tried reinstalling.

Anybody else experiencing this? How do I fix it?

its probably a steam error

Did it do that after validating all the files? I got that with TF2, also looking for an answer.

Im getting the same problem It’s probably is just a Steam Error.

Getting the same issue myself. Inside your first Gmod folder is hl2.exe . If you run this file, it will try to start up, but it should throw an error instead of just hanging.

The error I get is

Setup file 'gameinfo.txt' doesn't exist in subdirectory 'hl2'.
Check your -game parameter or VCONFIG settings.