Chances are that you had this question answered, however, I have worked in the glass business for the past 35 years. We have found that the epoxy (glue), that you buy over the counter in the auto parts stores, does not hold the rear-view mirror on. If it does, it is only for a short time and then it falls off again. You need to take it to a glass shop. Most glass shops will do it for free for you as a courtesy. You especially want to go to a glass shop if the bracket has fallen off your windshield too. This is the little metal piece that is glued to the w/s that the rearview mirror slides on to. It will take them just a few minutes (10-15) to do this for you and no headaches!! They can plug in any connections you may have on your mirror and you won't have to wonder if you are getting them in the right place. Just make sure that you go to a glass shop that does auto glass. It is a special type of glue they need to do this and a glass shop that does not do auto glass may not have the glue. Good luck to you and I hope your mirror stays on for you.
Sincerely,
Krissy
Actually already fixed it and no that is not the answer but possibly did not understand the question. The rearview mirror came off of the part that was holding it to the windshield. It does go back on but extremely difficult to attached it back. Perservance worked!