Anti-thief lock

I purchased my Dell inspiron last July for a University. I was set up & ready to go. I used it for classes. Went on Thanksgiving break & when I went back on the laptop it was fine when all of a sudden a screen came up & locked me out.
It has one paragraph stating I left it down for over two weeks & have lock me for anti-thief. It needs a code or password from the person who set it up.

For the last six months & have checked with the school & they don't get involved.
Sent it to 2 different Geek Squads & gave them the receipt & then could fix it.
I gave it to a personal computer co. with receipt & they could not fix.
I have call Dell, Inspiron, Intel, and about 30 different #'s. no resolve. they say they will transfer me & hangs up.
I want to send it back to Dell & have fix it & send it back to me. ??? don't know how.


Help Help Help Please.
Any one that can direct me to the right place I would be grateful.