i just had this problem for the first time too, I think it was because I didn't fill the liners enough.
Hi, i leave mine in the tin until they are completely cooled. I find that helps because that used to happen to me also, but since leaving them they stay in place.
I made 1,000 mini cupcakes a week ago for a charity food festival. I used mostly my real heavy duty commercial pans, but needed more so I bought 8 of the Wilton mini pans to make sure I had enough. I knew exactly which pans were used for which flavor. The ones made in the Wilton pans had the liners peel away. This did not happen on any of the heavy duty pans. I believe it is not a matter of underbaking like I used to think, but that the average home pan does not get hot enough to properly bake the cupcakes, even though they are baked til done.
If you want to prevent peeling, buy the heaviest pans you can get. Stay way from dark pans. Gravitate to dullish shiny pans rather the very shiny pans. I no longer have a problem since I stopped using the flimsy, cheap and dark Wilton pans. There is something about how hot the baking pan gets that helps seal the liners to the cupcake. And a lightweight thin metal pan cannot get as hot for as long as it needs to properly make sure the cupcake liners adhere.
I baked cupcakes last night in Wilton pans. The liners were fine and in tact when I put them in a container before going to bed. They were completely cooled. This morning the liners were peeling away. I wonder if I go ahead and ice them and put them in a box instead of an air tight container if it would make a difference. Although, I do think Linda's on to something.
I used to leave the cupcakes on the counter to cool, never thinking about the condensation that could develop under the warm cc and getting the liner wet. It never soaked the cc liner but it did make it flimsy. I finally realized I needed to put them on the wire racks to cool.....duh me. Also for some reason, leaving them in the pan to cool worked better for me also. I think with the pan being the same temperature that they both cooled together and there was no condensation to make the liner loose. HTH!
Read this thread about pans. http://cakecentral.com/cake-decorating-ftopict-724588.html I just bought my Gold Touch pans from William Sonoma. They are pricey but worth it. You can also by the USA pans from Sur La Table. They have the Platinum finish. I chose WS because I know they excellant customer service. I have seen the regular USA pans in stores and they are not near as heavy as the ones they make for WS and SLT and usually cost the same. Also, may want to look into buying cupcake liners that are Swedish paper. I researched recently. Also, Cupcake Creations makes excellant liners. The only thing is they are high in cost and you can't buy in large quantities. I bought in quantity from Qualita Paper Products. There was also another company recomended on here, Viking Importing. However, I had problems viewing the web site because of security issues.