Closed Door that should be Open

[darkart]

I'm in the Follow Freeman part of HL2. I'm at the point where you have to knockout the 3 generators to drop the shields. The three generators are in different rooms. 2 are easy to get to but the third is guarded by the red laser. Unfortunately I died the first time I attempted to reach this generator. But when I went back for another attempt the metal sliding door is closed and I can't find another way of reaching the generator.

Does anyone know how to solve this problem?

 

[Beerdude26]

You are supposed to die when you touch the red lasers. You probably accidently activated them and the metal doors closed. Reload from a previous save, and if that doesn't work, you'll have to replay that chapter