Cannot run adb command in ubuntu adb server is out

Question

when i run adb devices

    adb server is out of date.  killing...
    cannot bind 'tcp:5037'
    ADB server didn't ACK
    * failed to start daemon *
    error: 

its the same as this error here . some of the comments say that try to adb kill-server then start adb again but it does not work in my ubuntu machine.

I have also tried killall -9 adb which is the correct answer of this question. It is also stated in the correct answer is the best solution is to change genymotion settings and point to sdk but in my case i already did it.

can someone help me get rid of this error.

Answer 1

any way in case if someone will see this post i want to point how really simple the solution by closing all the genymotion devices then running the command

killall adb.

By killing all the adb does kill it all then i did

start-server maybe i have another adb running some times before and i forgot about it.