Chosen Solution
My printer will not print as it thinks its out of paper. The paper tray is full. Why does it think its out?
For the following models: HL-2130, HL-2135W, HL-2220, HL-2230, HL-2240, HL-2240D, HL-2250DN, HL-2270DW and HL-2275DW , see this post: HL-2280DW paper feed not working
Check by the feed rollers and look for a black plastic lever, this is the paper detect sensor. The lever should be easy to see if you remove the paper. It should move freely if it is working correctly. Sometimes this lever gets knocked out of its pivots when removing paper, if paper jams are not removed correctly then the levers might get broken off.