How can I safely re-heat a chicken pie without burning the crust?

Foil is the way to go, combined with not too fierce a heat. You want to cook at about 160°C (320°F) until the centre of the pie is piping hot. To lower the chances of burning, portion the pie prior to reheating. That way the centre will get hot more quickly.

Reheating more than once is generally not a good idea for safety reasons. You can however portion one night's pie and keep the other in the fridge.

Last time I tried to re-heat a pie in the oven, even with foil over it, the crust burned and the insides of the pie were still only lukewarm after 10 minutes plus.

It sounds like your heat might've been too high, or you put it on grill instead of regular oven elements?

Anyway, what I would do is microwave it for part of the reheating time. It helps to retain moisture, so things won't dry out as much. It can make the crust soggy/soft, depends on what's in the crust, but after warming it up to get the insides pretty warm, then finish it in the oven to dry up the crust again.

If you time the proportion of microwave to oven well, you'll be able to get toasty insides (but not dry) and a good crust (and not burnt!)

One alternate option is to heat it up again on stove-top. Just cut of your portion, plop in in a skillet, and heat up that way. I might even put it in a cool or warming pan, no need to wait for it to be already hot since it just needs warming, not cooking, and pie crusts generally have enough fats to be fairly non-stick.

The bonuses - the skillet will warm from the bottom up. It's nice for keeping the bottom crust from getting soggy while reheating (or drying it out a bit if it was already soggy), and making sure the middle is warm, while the top stays nice and un-scorched. It's also faster, as direct exposure to heat will warm the food faster than the oven, and it will also dry out the pie less.

We sort of got the idea from someone singing the praises of reheating pizza on stove top, but since then there have been pies successfully heated with this method, both sweet and savory (it is especially nice if the bottom crust can use a bit more crisping up). Wetter pies are a bit messier, but it still works.

if you glass oven dish or bake pan, Take out one serving and heat to 30sec-45 sec . Popped into oven or toaster oven. If you put in oven you need to watch like 5-10 minutes or more.

Heat your oven to 200 degrees then put your pie on a tray to put in the oven for about 30 to 40 min. Check middle of pie to see if hot if not cover edges of pie with foil and leave in for another 10 min. Continue checking every 10 min. until hot.

It took me one hour, at 160°, to reheat half a fish-pie, which I cut in half, so it would heat through more evenly, and covered with foil. I removed the foil for the last 10 mins. It came out just perfect.