not finding android sdk (Unity)
Unity 5.6.1 / 2017.1 fixes the Android SDK Tools 25.3.1+ compatibility issue. This is noted in Unity bug tracker under issue 888859 and their 5.6.1 release notes.
The issue is due to incompatibility of unity with latest Android build tools. For MacOS here's a one liner that will get it working for you:
cd $ANDROID_HOME; rm -rf tools; wget http://dl-ssl.google.com/android/repository/tools_r25.2.5-macosx.zip; unzip tools_r25.2.5-macosx.zip
1- Just open https://developer.android.com/studio/index.html
2- scroll down to the bottom of that page
3- download last version of tools for your OS (for example tools_r25.2.3-windows.zip)
4- Unzip it
5- Delete folder tools from previous Android Sdk folder
6- Copy new folder tools to Android SDK Folder like this image:
I have same problem.
I fixed by android sdk tool version downgrade.
The steps.
Delete android sdk "tools" folder : [Your Android SDK root]/tools -> tools
Download SDK Tools: http://dl-ssl.google.com/android/repository/tools_r25.2.5-windows.zip
Extract that to Android SDK root
Build your project