How to unlock green lockers in Silent Hill: Downpour?

Solution 1:

The reason you don't have the password is that you actually can't obtain them in the game - this locker is actually a sneaky way of unlocking bonus content. These codes were available with preorders, but obviously they're universal. You might try any of the following (I've left the actual weapons you get as a surprise for the curious): 353479, 171678, 911977.

You are likely to run into a few more of these as well; they'll all use the same set of codes, I believe. (I am unsure if you can use a code twice but I expect the answer is 'yes'.)

Solution 2:

You can type in the code 911977, then you get a repeater and a 9 iron.