"Built with udk has stopped working" error

Everytime i try to open a file in UDK I get this error and UDK shutsdown. I run UDK with Admin rights, and have only just started getting this error. I have tried to open other files but I still get the error. This is not the first time I have seen this error. But I cant remember how I fixed the error last time.

I get an error in the log file missing. I haven’t herd of this file before.
[0030.44] Critical: appError called: Failed to find object ‘World A4_Level_Prototype_R01.TheWorld’
[0030.44] Critical: Windows GetLastError: The operation completed successfully. (0)
[0082.57] Log: === Critical error: ===
Failed to find object ‘World A4_Level_Prototype_R01.TheWorld’

Please post this in UDK forums. AnswerHub is for Unreal Engine 4 reports/questions.

https://forums.epicgames.com/forums/366-UDK

I’m sure you can get an answer even by searching the forum. Good luck!