Android Builds ends up with error

I just downloaded and tried to build an android project on Unity 2017.2.0f3 but I ended up with errors;

JDK and Android sdk downloaded and referenced at Edit+Preferences.

I googled and downgraded tools to 25.2.3 and 25.2.5. None of them worked.

Please help

Any suggestions?

In unity goto edit > preferences, click external tools scroll down and click browse beside SDK and find your installation folder. For me it was C:/Users/PutYourNameHere/AppData/Local/Android/sdk

Hope this helped.