Following this answer, I have tried restarting a Jenkins instance using:
(jenkins_url)/safeRestart
and
(jenkins_url)/restar
Restart your command prompt in Administrator mode. So that you are having your all permission to run window as a service.
If your Jenkins instance's servlet container does not support a web application restarting its own context, then this plugin cannot provide restart functionality, and the “Restart Safely” link will not appear.
I'm using Apache Tomcat v7.0.64 and after installing SafeRestart Plugin I got the same message as you had.
I think it would be much simpler for you if you just run Jenkins with the embedded container and the service wrapper
I received such message when jenkins was started in command line (like java -jar jenkins.war)
After I started jenkins as a service (jenkins.exe install) and (jenkins.exe start) it began to work.
I installed Restart Safely plugin available in Jenkins Plugin Manager
Jenkins -> Manage Jenkins -> Manage Plugins -> Search for Safe Restart -> Install it.
Then Go to Manage Jenkins -> "Install as Windows service" -> install
Then Restart Safely appear on the Dashboard. Thanks to Shwetank Singh.
To manually restart jenkins :
I happen to face this problem where restart was required to update jenkins version , I tried by url but faced the error - jenkins cannot restart itself as currently configured. Tried above mentioned steps and it worked.
Go to Manage Jenkins links. Find the option "Install as Windows service". Click on install. Now (jenkins_url)/restart option will work. I faced this same issue now