Weird Half Life 2: Episode 2 Shadow Error

I recently reinstalled HL2: Episode 2 after I accidentally deleted it. But When I did, things got really weird. First, the desktop icon doesn't show anything. But the main problem is that now all the shadows created by the flashlight have really grainy looking outlines. I have played the game before I reinstalled it and know that the shadow is not supposed to look like that. Reinstalling the game again didn't help.
heres an image of the grainy shadows: https://support.steampowered.com/at [...] ?id=355425
If you look at the chair's shadow and Alyx's arms, you can see what I'm talking about.
Any suggestions of what to do?