Default Pawn Class not working

So I decided to update Unreal from 4.8 to 4.15 in the middle of a tutorial, and my game will not play.
this is what it originally looked like:

And here it is after:

Notice the String in the upper lefthand corner. THAT came from my Macro that handles reference casting. The IsValids were added to isolate where reference casting was breaking (The Dreaded Accessed None Error) and I found that the error comes from GetPlayerPawn failing. I assume this is an issue with Default Pawn Class I deduced this because when I change my DPC from CameraPawn (the pawn with the camera attached to it) to Default Pawn I successfully get Player Pawn, but fail to cast it (because the node is for casting to Camera Pawn…I think):

So I know (think) the problem has something to do with my CameraPawn, but I have no idea if I’m right or not, or how to proceed.

Maps and Modes. Because it’s been asked for every time someone asks about Default Pawn Class

I have the same issue, I’m pretty sure it’s the CameraPawn not getting initialized when you attempt to cast it. I tried to see if it ever becomes valid by tracking the camera pawn with the tick event: it never seems to become valid in some instances. Have you found a method to overcome this issue?

In case anyone else has this issue and finds this post, here’s what worked for me:

If you drop a pawn into the scene, you need to set that as the default pawn. You do this by selecting the pawn actor in the scene, then scroll through the details panel to find Auto Possess Player. Set it to Player 0.

Thank you to [Nachtmahr][2] for this solution.