Jenkins Failed to locate Cygwin installation. Is Cygwin installed?

You configured a new Windows  (64 bit) node in Jenkins  (either run as Windows servvice or JNLP or ssh) and when you try to execute a shell command from it, you may get the below mentioned error.

FATAL: command execution failedhudson.util.IOException2: Failed to locate Cygwin installation. Is Cygwin installed? at hudson.plugins.cygpath.CygpathLauncherDecorator$GetCygpathTask.getCygwinRoot(CygpathLauncherDecorator.java:122) at hudson.plugins.cygpath.CygpathLauncherDecorator$GetCygpathTask.call(CygpathLauncherDecorator.java:127) at hudson.plugins.cygpath.CygpathLauncherDecorator$GetCygpathTask.call(CygpathLauncherDecorator.java:112) at hudson.remoting.UserRequest.perform(UserRequest.java:118) at hudson.remoting.UserRequest.perform(UserRequest.java:48) at hudson.remoting.Request$2.run(Request.java:287) at hudson.remoting.InterceptingExecutorService$1.call(InterceptingExecutorService.java:72) at java.util.concurrent.FutureTask$Sync.innerRun(Unknown Source) at java.util.concurrent.FutureTask.run(Unknown Source) at java.util.concurrent.ThreadPoolExecutor$Worker.runTask(Unknown Source) at java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source) at java.lang.Thread.run(Unknown Source)Caused by: hudson.util.jna.JnaException: Win32 error: 2 - null at hudson.util.jna.RegistryKey.check(RegistryKey.java:124) at hudson.util.jna.RegistryKey.open(RegistryKey.java:223) at hudson.util.jna.RegistryKey.openReadonly(RegistryKey.java:218) at hudson.plugins.cygpath.CygpathLauncherDecorator$GetCygpathTask.getCygwinRoot(CygpathLauncherDecorator.java:115) ... 11 more

You can try the fix provided in the link https://issues.jenkins-ci.org/browse/JENKINS-6992

If you are still getting the same issue, then check in your Jenkins shell, whether you have
#!/bin/bash
in the first line.
If you have this, remove it. Your shell script will work fine.