If you are connected to a VPN, disconnect and then try to access Jenkins on the browser with URL localhost:8080. If you have installed tomcat in your windows, then you will have to stop the tomcat service or change the port of either tomcat or Jenkins (as both these services by default run on port 8080) and then access Jenkins on the browser.
Simply restarting Jenkins solved my problem. I followed the below steps,
- Open the command prompt as an administrator
- Execute the below commands,
cd C:\Program Files\Jenkins jenkins.exe stop jenkins.exe start
- Wait for some time and then access the Jenkins dashboard.