Why isn't my Kingoroot working

[AC Question]

I am on my Android Kitkat (4.4.2) the first time it worked then I unstalled it. A few weeks later I had got it back then it was just a pitch black screen. Then I deleted it again, and forgot about it, remembered, got it again, then it acrually showed the main screen, I clicked one click root, nothing happens until I click it again, I wait a few seconds and then the app stops.

 

[Rukbat]

First, Kingroot just goes to its server looking for a rooting method that will work on your phone using your version of Android. If they removed it (4.4.2 is a bit old), you can no longer use Kingroot.

Second, Which phone? There are still rooting methods available for some phones running 4.4.2, but they're different programs for each phone. Without knowing which phone you're running, we can't give you anywhere to look, except XDA Forums.