Generally there are three possibilities (apart from the battery
going bad) that can cause your remote not to charge:
1) Some folks have reported that the battery
is not sitting tightly enough in the battery
compartment. You can try folding a small piece of thin cardboard and place it between the battery
and the back of the compartment. This will push the battery towards the front of the compartment and create a tighter connection
against the contacts.
2) There have been reports of problems with some of the charging cradles in which the remote does not make sufficient contact with the contacts in the cradle. To ensure that the remote begins to charge, place it in the cradle and listen for a single beep. The slide show
should start and then, after a few moments the screen should darken. If you hear two beeps at any time, it means that the remote has lost contact with the charging cradle and has 'woken' and is no longer in charging mode. Wiggle the remote to ensure that it is sitting in the cradle and making contact. There are also some fixes that can be done of the cradle itself, including opening it up and adjusting the height of the contacts. Others have had luck cleaning the contacts on the remote and the cradle with alcohol or a contact cleaner like DeoxIT. Still others have actually sanded down the plastic surrounding the contacts on the outside of the remote in order to bring them closer to the cradle contacts.
3) If you still have trouble after you have tried everything above, there may be a loose connection
inside the remote itself. There is a very small plug that connects the charging terminals on the remote to the battery compartment. In some cases, this plug can become loose (especially if the remote has been dropped). If all else fails, you can open the remote and check to make sure that the plug is completely seated or attempt to push the terminal contacts slightly farther out. However, most people have found that altering the height of the contacts on the charging cradle is a better way to go. If you want to open the remote, do the following: remove the two screws - one in the battery compartment and one at the top of the remote. Then, using your thumbnail (this is really the best, unless you have a thin, rigid piece of plastic. A part of a credit-card may work), force your nail between the two halves of the clamshell casing near the bottom of the remote on the left or right side. Once you get your nail (or plastic) into the remote, angle it down at about 45 degrees and simply slide your hand up one side. This will release all the locking tabs very nicely without marring the surface of the remote. Then do the same on the other side. Once you are done exploring, simply realign the two halves and snap them back together. Good Luck!!