After purchasing the replacement bulb I had a lot of problem removing the cover.Turns out that three of the six screws in the back required a special tool. After trying different types of screw drivers to no avail, I took a picture of the screw and went to my local hardware store for some help. I had previously tried different sizes of Torx screw bits but none worked. It turns out that the screw was a Security Torx (has a center post in the middle of the screw) and required a TT20 bit, I was able to open the microwave cover and replace the lamp,by removing just two screws that held it in place and installing the new lamp in less than 5-minutes. I now have a security Torx bit set for toolbox for future use on other things. I almost threw in the towel and thought about calling in an appliance repair man due to the time spent (2 hours) going to several different hardware stores looking for the the right tool.