ADB server didn’t ACK * failed to start deamon*

Are you encountering the following errors with ADB?

Windows Command Prompt

c:androidsdkplatform-tools>adb devices
adb server is out of date.  killing...
ADB server didn't ACK
* failed to start daemon *
error: unknown host service

Solution:

ADB server cannot start if port 5037 was occupied by other process hence we need to find and kill the process to release this port.

c:androidsdkplatform-tools>netstat -aon|findstr 5037
TCP    127.0.0.1:5037         0.0.0.0:0              LISTENING       6889
TCP    127.0.0.1:5037         127.0.0.1:50506        TIME_WAIT       0
TCP    127.0.0.1:5037         127.0.0.1:50507        TIME_WAIT       0

PID 6889 is occupying port 5037. Find the process and kill it.

2. Start ADB server

c:androidsdkplatform-tools>adb start-server
* daemon not running. starting it now on port 5037 *
* daemon started successfully *