I have the same problem as the original poster in that the orange button goes down when pressed but then slips just a little to the side and won't come back up.
I've made it come up by pounding on the case next to the button with my fist, by jiggling the button with the eraser end of a pencil (usually resulting in it ruining the printing of the booklet I am trying to print by printing a test page), by grasping the side of the top casing near the button and trying to flex it, and by using a pocket knife to try to make the button's hole bigger in the casing. It finally got so bad that nothing I would do would make the button work.
So I took the top off and found out that the "orange button" has an offset part that is what actually contacts the switch, and that the orange plastic part is mounted in a clear plastic piece which also acts as the lens portion for the red and green lights. The clear plastic piece is attached to the cover with two screws.
Over time, the clear plastic piece had broken in half, allowing the part holding the orange button to swivel. This initially was what would cause the button to get hung up under the hole and not able to come back up, and eventually through all my efforts to make it come up it moved the portion of the orange button that contacts the actual switch far enough that it no longer would make contact.
Three possible fixes: 1. Order a new clear plastic piece from Samsung. 2. Glue the clear plastic piece back together and hope it holds. 3. Go the ugly but sure route of removing the broken part of the clear plastic piece along with the orange button and spring, and cut the top open between the button hole and the edge so that the actual switch can be reached.
I chose number 3: This will void your warranty, but mine was way out of warranty anyway.
First, I turned the printer off and unplugged the power cord.
I took off the top, by opening the front panel of the printer where the toner cartridge is installed, then removing the two screws that hold the front of the top down. Then it was a matter of daring to break the plastic of the top panel in freeing the plastic tabs so that the panel could be removed.
I found that by lifting the front until the side tabs gave way and then removing the hinged cover where the paper comes out, I was able to finagle the top off without damaging anything. It probably would be easier to remove by taking the screws out of the black rear cover and so forth, but this worked.
Next, with the cover removed and turned upside down, I removed the screw holding the broken portion of the clear plastic piece and removed it along with the orange button and spring. I left the other half in place so that it would transmit the light properly for the red and green lights.
Then, taking my trusty Leatherman tool, I used the saw blade to open up the area between the button hole and the outside edge of the top. I used the Leatherman's file to smooth off the rough edges.
Next, I reassembled the printer (this was probably the hardest part - and at this point is when I realized that taking the back off would maybe make things easier, but if you aren't afraid to torque the plastic a bit it will all snap back into place), plugged it back in and fired it up.
I printed a test booklet. First side printed normally, the red light came on as it should. I removed the paper and reinserted it, then used a pencil to reach in and press the switch. Success! The second side then printed!
The problem is solved! The printer looks a bit worse for wear, with a big hole where the button used to be, but that is of little matter to me.
Because there may be a danger of electric shock, I would advise that if you choose this repair method you use a pencil or other stylus to reach in and press the button on the switch instead of using your finger.
You may find that it will take a bit more pressure than you think it will to actually trigger the switch.