When running a 3" screw

Look at the wood screw threads and hold a drill bit against it. Choose a drill bit that is smaller in diameter than the threads on the screw. Works for any size wood screw.

Some screwguns have a torque adjustment that slips when adjusted too light. The strongest setting usually has a symbol of a drill bit. Have you tried putting the screw into another piece of wood? If you are going into a very dense wood you may have to predrill hole.

I experienced the same problem. The solution was easy, for me at least. Remove the door. pry loose the plastic liner that covers the inside of door. remove the four screws that hold the glass unit in place. You will find rattling around inside a spring about an inch long and a broken plastic piece about an inch and a half tall. On my unit the plastic piece was still hanging on by a thread which gave me a clear understanding of how the door latch is supposed to work. Remove the plastic latch unit which is designed to slide on the two posts about three eights of on inch distance under the pressure of the spring. Problem is loss of spring induced pressure.
The repair: ( I used my bandsaw to do this) fashion a piece of wood with indentations that correspond to the plastic ribs enabling the wood to sit perfectly into the space. Drill a hole at the point where the inch and a half "anchor post" broke off and insert a dowel of same length. I carved a shallow indentation for the spring, pressed the spring on with needle nose pliers, replaced the sliding latch mechanism, attached other end of spring to the latch. I drilled into the exterior plastic door frame and installed a flat head screw to hold the wood repair piece solidly in place. Re-install pieces removed earlier and you have a happy, functioning Frigidaire gallery micro at your service. Took an hour.

My solution when the other mentioned ideas didn't work was this: I removed the 7 Torx #20 screws ( a common screw driver will work as well) and removed the housing half to expose the shaft. The chuck shaft bearings and gear lifts out as one assembly. Directly behind the chuck there is a half inch section of shaft exposed. I mounted a vise grip on the shaft (won't hurt it) and clamped the affair in a bench vise. With a 5/16" allen wrench mounted in the chuck and using a mallet I spun the chuck off with a solid smack counter clockwise . Very simple and easy .

its fried - return /exchange

The screw is either broken ,the hole stripped out, or screw not into something solid.Try prying up under the screwhead with something as you turn it with the drill

Sorry, there are no rules as to what to set torque to for your job. There are too many variables like thickenss of the wood or drywall or the hardness of the material you're driving into and whether you want the screw to stop above, at or below the surface. The best thing to do is set it low and raise the torque untill it stops when you want it to. Keep in mind if you hit something like a knot it will stop the screw earlier and if you go through a softer spot in the wood it will drive in deeper.

hold the drill so the handle is facing you and the drill bit is facing away then twist the chuck clockwise. some quick chucks have two halfs in which case you hold the back collar (nearest you still)
if its really tight it the drill bit into the chuck with something soft like a piece of wood so as not to damage the drill

no i dont think you are doing any thing wrong ,it is typical of the product you bought .