This is a first for me. I've got dozens of semi-autos and never had this problem......
Just picked up my new M&P 9c yesterday. This morning I did the field strip to remove the packing grease (oddly, there was none). Anyway, I'm familiar to the basic procedure of taking down the pistol as I own a Shield which is similar, i.e., the "sear deactivation lever" must be down into the mag well, etc. I lubed the gun, then reassembled. I did note that at some time when I was lubing, the sear deactivation lever somehow flipped to its up position. I did not pull the trigger or manipulate any of the other controls, so I suppose it just flipped down as I was rotating it around to lube it. I put the deactivation lever down again, and reassembled the gun. No issues there.
I inserted the magazine (which pushed the deactivation lever up), and attempted to have the slide go forward using my left hand to draw it back, then release it. Nothing. So then I tried depressing the slide stop lever...first one side, then the other side. Nothing...the slide stop button will
not go down. I then tried using my left hand to push the slide back while depressing the slide stop lever. Nothing. No movement in the slide release button at all.
Then I removed the magazine (slide stayed back as it should). I then repeated the two methods of releasing the slide without any problems. I did note just using the slide stop without assisting with my left hand was a little difficult, but not much for a new handgun.
Any ideas? I know I can call S&W but I figured I'd ask here first, hoping it's something simple than I screwed up and can easily fix!
Oh, I did field strip a couple of times before I wrote this, hoping I could correct whatever problem is there to correct......