Mint Kodak 650H slide projector shutter door stuck closed. Both the remote and side buttons forward but won't reverse-both reverse buttons forward why ?

SOURCE: Kodak Carousel 760H wont advance or reverse

Yeah. I like the $15 fix better. Go to Ebay and search for "Kodak Carousel Projector Advance Repair Kit". Before you purchase you can diagnose, and it comes with detailed instructions. The same guy also has a kits for other common problems, as well as the "tune up kit". Or you can buy the Solenoid Link, directly and try it without detailed instructions.

SOURCE: Kodak Projector 760H. Carousel won't

Chances are that your projector has a broken solenoid "link". This "Link" connects the slide change solenoid and the slide change mechanism. Over time this part becomes brittle & cracks, rendering the slide change non-functional. A pretty easy fix for an authorized repair dealer.

SOURCE: Automatic slide changer is stuck in

The problem is continuous cycle (like you don't know that already...). It indicates that an adjustment to the cycle contact is necessary. To open the projector, first unplug it and remove the lamp module from the rear of the projector. Turn the projector upside down. Remove the 6 - T15 TORX screws from the bottom (5 around the perimeter and one in the channel next to the cord wrap). CAREFULLY pull the bottom off (the power wires connect the bottom cover & top together!!). Once you have it open, leave the projector upside down, put on your safety glasses & plug the projector into the wall. At the center of the projector you should see a hub rotating about every second or so. Above it you should see a "J"-shaped wire. See the attached illustration.
You will have to, in repeated steps, unplug the projector, bend the "J"-shaped wire GENTLY & SLIGHTLY, plug the projector back in and cycle it a few times. Check for the position of the "J"-shaped wire to the pad, and GENTLY repeat until you achieve the position shown in the illustration.
Good Luck !!

SOURCE: Kodak Carousel 760H wont advance or reverse

You have jammed the slide change mechanism. Turn the projector off. Remove the tray using the emergency release slot in the center hub of the projector. Turn the projector on and cycle it a few times in reverse, then in forward. That usually clears a mechanism jam.

SOURCE: Projector works fine, but will not advance slides.

Try a different tray (preferably a Kodak 80-slide tray). If it works, then the problem is a tray problem. If it makes no difference, check the "SELECT" function. If that works, then your projector requires an adjustment to the slide change mechanism. If it does not work, remove the tray and push the "REVERSE" button 4 or 5 times (this will clear a mechanism jam if one has occurred). If you still have nothing, then chances are that the slide change mechanism drive belt is broken or stretched. try the diagnostic things I suggested. If they are no help, I'm sorry to say you need the help of a factory-trained repair dealer. Good Luck !!