Try lightly greasing the mold first. Then, pop the filled mold into the freezer for about 5 minutes or so. Your fondant should come out easily.
Edited to add: The reason it never set up after a week is because the fondant inside the mold was not exposed to air, so it never dried out. As long as the fondant is soft and sticky, it won't come out of the mold unless you've greased (or cornstarched) it first.
I have the Wilton fondant letter mold. Diane is right - you need to freeze it for a bit, and then try using a toothpick to slowly pry it out. Put it at a slight angle so you catch it.
The letter mold kit comes with a dull edged tool to do this, but a toothpick should work - just don't push it all the way thru or you'll puncture the front. Just catch it on the back, pull slowly at a slight angle, then use some Crisco to smooth over the hole if you need to.
Good luck!
Forgot to add: I don't think you need to coat the mold with anything if you're freezing it. I do both fondant and chocolate molding and have never need to do that. The chilling is what hardens it up. Plus cleaning grease out of the little nooks and crannies is a pain in the backside.
Good luck!
The fondant also works better if you add some gumtex or tylose. It makes it a bit firmer and less sticky. You can also lightly dust the cavity with some cornstarch as well as the fondant just before you push it in. Putting the mold with the fondant in it also helps.
I use Pam spray on the molds, and after the fondant is in, I use a little rolling pin over it, then run my finger around the edge of the mold to make a nice clean edge. The fondant comes right out, and as long as you've wiped the pam spray with a paper towel before you put the fondant in, the grease absorbs and doesn't look shiny. I didn't put it in the freezer.
I did the molded details on this cake with a candy mold and pam spray:
I use Pam spray on the molds, and after the fondant is in, I use a little rolling pin over it, then run my finger around the edge of the mold to make a nice clean edge. The fondant comes right out, and as long as you've wiped the pam spray with a paper towel before you put the fondant in, the grease absorbs and doesn't look shiny. I didn't put it in the freezer.
I did the molded details on this cake with a candy mold and pam spray:

Thanks again!!!!
This cake is wonderful!
OMG, where were you guys a couple months ago when I was trying this! I couldn't get the fondant out of the candy molds & finally gave up - so glad I didn't throw them away. Can't wait to try the freezer thing!
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