Thanks OS-Wiz. I have the same issue with overhand racking on my M&P Pro 9mm. It's funny, there was a very long thread on this forum that started when a OP questioned whether there was something wrong because his "slide release" didn't work on his M&P Pro. Everyone jumped on him claiming it's a "slide stop" button and was never meant to be used as a slide release even though it's located on both sides of the gun. I shot 6 semi-automatics this weekend and only on my M&P could I not use that lever to release the side. The guns included a .45 Colt Gold Cup, a Kimber .45, my XDS, my Beretta 84, a Sig P238 and my M&P Pro 9mm. All the others released very smoothly. BTW, the OP who started that thread found another thread that has a solution to fix the M&Ps and got his working fine. Regards, Elliot45.