I'm new to solidworks and am having problems getting two parts to mate correctly in an assembly. The assembly consists of a plate with four countersunk holes in it, with corresponding quarter turn fasteners (dzus) inserted into the holes. Both parts, on there own are fully defined. When I add the dzus to the plate, I can get it aligned properly but solid works states that it is under defined. I can not understand why. Any help would be appreciated. The dzus part file came from the company that makes the item, just so you are aware.