I'm having issues mirroring my mesh
I'm trying to attach a skeleton to a character that I purchased from a 3d modeling website, so I can send it over to MotionBuilder to make animations. I added a skeleton by using the template created when clicking "Create Skeleton" in the Human IK menu and scaling it to my character's size. I’m having an issue with my character because it's positioned differently than the T-pose that is required to make animations with in MotionBuilder. I moved my character's mesh on the left side to be positioned in the T-pose so I could mirror it on the other side to be in the same spot, but whenever I mirror it under the "Mesh" tools bar, it doesn't fully mirror my character. There are small pieces of his hands and arms that stay in place after the mirroring is done. I’ve have links to several screenshots below to show what this looks like. I checked to see if the transformations where frozen, or if the objects were locked, but this wasn't the case. I also tried mirroring the mesh in the opposite direction, but it does the same thing.,There was also controls that came attached to the character, and I deleted every single control so it was just the mesh, and I was still experiencing the same thing.
I'm not sure exactly why this is happening, so if anyone could tell me what I'm doing wrong, I'd greatly appreciate the help.