When I print the paper comes out the top rollers about 3/4 of the way and then stops. The printer then generates a 077-900 paper jam error. When remove the paper & open the front cover to clear the error, it merely prints the page again with the same results. I have tried cleaning the rollers with alcohol.
What size paper are you using? Also, does the paper size in the printer match the page size in the application? (very important !! paper size mismatch can cause this problem)
Are you using the tray or the MPF in front?
Can you print the internal settinsg report with no problem?
Using alcohol on the rubber parts is bad. It may work great for a little while, but tends to dry out the rubber and will decrease the overall life of the rubber parts used in the printer. Use a mild soap/water solution on a lint free rag (an old clean tee-shirt is perfect), dampened enough to be effective but not enough to drip liquid inside the machine. After cleaning, then use another rag slight dampened with regular water to remove any of the cleaning solution residue. Repeat as needed.