It's not clear if you can't get the embroidery arm to open, or if it opens but will not move the hoop. In the case of the arm refusing to open, it could be that the hoop attachment point is not in the "HOME" position. Normally this happens when you turn the machine on. If you push the lever to release the arm, and nothing happens, it may be that problem. However there could be internal issues as well. When we unboxed Diane's 12000 years ago, the arm refused to open. I discovered that a screw had come out during shipping, and was preventing the lever from working.
One problem that happened more than a few times on the 11000 is the plastic strip that covers the opening in the embroidery carriage to keep lint out. Over time it may start sticking, and at some point it will just crumple up like an accordion. At that point replacement is required.
Your best option is to take the machine to a technician, since there is almost nothing you can do yourself.
