reviewed Content errors.

Before you ask, yes I have typed !content and installed, reinstalled the addons after some issues. I can't figure out why certain player models dont work. Specifically security guard, the 50s and the nightclub manager playermodels arewn't loading?

 

Any ideas of what i could do?

I suggest you check if CS: Source is downloaded and mounted onto your game beforehand. Here is a clip

 

Make sure you go through your addons and ensure that they are all green. This means that they are all good and no errors have been detected. If it is a different colour then it has an error and need reinstallation.

Failing everything, ive done this before and its fixed weird issues.

 

Ensure CSS, TF2, etc are all installed (or gamefiles added)

Save your GMOD addons file into a separate area so you don't lose everything.

Remove your addons file.

Join the game.

Do !content again.

Exit Gmod completely.

Verify integrity of game files through steam (right click Gmod, go to properties)

Re-join server

I actually had a similar problem when I joined the server! There is a setting in the options menu that changes what the game will download when you join a server (Options>Multiplayer>Allow all custom files from server). I had it set to map only but when i changed it to allow all custom files it got all the missing content. Of course, definitely make sure you have either the games or gamefiles for CSS, TF2, and possible HL2 as Tuppy mentioned.