adb server version doesn't match this client

Question

Whenever I try to run adb devices:

            $ adb devices
            * daemon not running. starting it now *
            * daemon started su         


        

Answer 1

In my case, the problem was caused by Virtuous Ten Studio, which has the adb.exe in External/ADB directory.

Go there and run .\adb.exe kill-server and you'll be good.