Key Pad Controls Stopped working---was repaired now doesn't work

We purchased a Dell 5100MP projector on 10/07/05 which subsequently had a malfuntion in the key pad controls in July of '07.  Dell support sent us to an authorized repair organization called Technical Service Corp. who reparied the projector for $670.  Just after their warranty expired (90 days) it failed again.  Now TSC does not even repair these projectors.

 

I'm wondering why Dell sent us to a repair organization that is ineffective and now doesn't even attempt to repair this projector?

 

What you do to help?  We have a dead $3800 projector which cost another $670 and now doesn't work....