Render stuck at same spot each time.

So here’s what I got: simple animation of a flyover on a transparent backround, with a quick explosion, no fire or smoke, no compositing. Nothing fancy, and I’m using CPU since the GPU was having an even worse time with the explosion. Everytime the render gets to the second frame of the explosion it freezes at 99% and sits there forever. I have tried messing with settings, deleting and restarting my render, but it always stops at the same spot. My PC is an I7-2600 3.4GHz 8GB ram. I just wanted something quick to practice with in AE. Can anyone offer any advice? Thanks.

how long have you waited?