Howdy!

Below is a link to a thread about hand pollination of squash. Now, I don't know, from your post, whether your pumpkin has been producing female flowers or only males. Squash and pumpkins produce both. However, oftentimes, for weeks they will produce only one or the other. If this is the case, you probably need only wait and it will come around and set fruit when it's ready. The reason I'm giving you the link is that in that thread there are photos of male and female flowers, so you can recognize what your plant is producing.

If by chance your vine is already producing both male and female flowers, but it still isn't setting fruit, then you probably have a lack of bees for pollination. If that's the case you can use the information from the link to do some pollination yourself.

If you are only interested in getting fruit, not necessarily pure seed, then you need not tape any flowers shut. All you'd have to do is apply pollen from male flowers to the female flowers and let them be. You'll get fruit.

Hope this helps! Squash and pumpkins regularly cause gardeners concern when they don't set fruit. Normally, it's only a matter of time.

George
Tahlequah, OK

Here is a link that might be useful: hand pollination of squash/pumpkins