If reinstalling the application doesn't solve this, the things to do are:
1. See if any of the hits on the first page of https://www.google.com/search?q="there+was+a+problem+starting" are useful.
2. Contact their tech support. After all, it's a paid game so there should be support.
I keep having seeing, failed to reset:
There was a problem starting C:\Users\user\AppData\Local\KingdomBuilder\Bin\KingdomBuilder.dll
I am running on Window 10. Please HELP!!!

Chowhound
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GameSpot
Giant Bomb
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