Microwave ovens generate high voltages (thousands of volts) and dangerous amounts of radio-frequency radiation. Attempting to repair one is NOT for the amateur tinkerer. I advise recycling or trashing it and getting a new one (they don't cost much these days.)
I had the advantage of already owning the iFixit Pro Toolkit before I started so I was able to remove the spring contact under the top screw with the curved tweezers (and re-position it before putting the screw back in). I also used the tweezers to gently hold the contact still while I tightened the top screw. I also had the 'Searching' issue on bootup but I figured it was a network contact initialization issue since the network data would be wiped so I set the phone to Airplane Mode for about 15 seconds and then switched it back. It connected instantly. Hope this helps.