When baking a frozen pumpkin pie you preheat the oven to at least 400 F.
While the oven is heating up take the pumpkin pie and make a few slits in the pumpkin pie so that it cooks better.
It's always best to bake the pumpkin pie frozen if it's already frozen because if you thaw the frozen pumpkin pie out then it can become soggy.
I've baked lots of pumpkin pies after I've froze them and baking them frozen is best and the oven will thaw them out and bake them.
Baking a frozen pumpkin pie takes around 45 minutes so it's best to set a timer and keep an eye on the oven and pumpkin pie.