How do I fix the open tray problem?

On the drive that I'm working on, the laser will light up, and when I load both game and movie discs it will spin for 1-2 seconds then stop and say, "Open Tray."

I have the drive open right now, and I've already cleaned the laser with rubbing alcohol and a couple cotton swabs, but that didn't fix it. I also blew out the drive thoroughly, and manually removed some dog hairs that had accumulated in the drive. So far I've had no luck figuring this one out.

I just tried manually re-positioning the laser, but it just goes back to its normal spot near the spindle motor every time.

I'll order a new laser, but hopefully I can do this without one.