Half life 2, episode 1 and 2 textures missing.

For some reason, when I go to the little game controller at the bottom right corner, All 3 half life 2 games have a folder with a red circle next to them. I can’t mount the games, though Left 4 Dead 2 and Team Fortress 2 have a box with a check mark next to them. I have bought all 3 games, installed them and have run them, but it still won’t work. They were mounted before this latest update but not in this one.

http://forum.facepunch.com/showthread.php?t=1271741&p=40947892

Follow this tutorial for all of your Half-Life games.