Hmmm. An interesting problem. Is there any sign of mildew on the tent? Was it packed tightly for a long period of time? It could be that some combination of moisture/warmth/tight packing has caused the polyurethane coating on the fly to deteriorate a little and become semi-liquid, and it’s now gluing itself together. It is my understanding that this was not uncommon in older tents—those made a decade or more ago. If it’s a very uniform stickiness, this could be what happened.

It could also be something else, something environmental when you last used it. So try this: Get a big bucket or plastic tub, fill it with warm water and a little Dawn detergent, and sluice the fly around in that for a while. Then rinse it thoroughly and air-dry out of the sun. Maybe some tree residue or something is causing it to stick.

If that doesn’t work, well, you have a problem. Depending on the age of the tent, it could be possible for you to order a fly replacement from the manufacturer.

Otherwise, it’s probably time to buy a new tent. Sierra Designs’ Meteor Light ($239; sierradesigns.com) is a classic two-person backpacking tent…really a great performer. I also like Marmot’s Aeolos 2P ($335; marmot.com), which has two doors and two vestibules for easy in-out and good gear storage. For something a little different, Black Diamond’s Lighthouse ($379; bdel.com) uses a highly water-resistant fabric with Nextec’s Epic treatment so that only one fabric layer is necessary. I’ve been using a Lighthouse this summer and like it a lot.

I always recommend packing tents loosely in a breathable sack—a cotton pillowcase works great—and most tent makers now include breathable sacks as well. It helps ensure the maximum lifespan of the tent.

You’ve seen our picks for 2007 Gear of the Year, and now the entire Outside Summer Buyer’s Guide is online. Check out this year’s more than 400 must-have gear items, including tents.