SharePoint 2010 - Service Unavailable - HTTP Error 503. The service is unavailable

Fix for HTTP Error 503. The service unavailble-

All my developement is through my SharePoint VM, and the server is configured to use service accounts as part of the best practices. So far so good, but what happens when the service account password has got changed after SharePoint installation.

As per our company policy password for my service account is set to expire every 90 days, and if I change the password of my service account, I will not be able to access my sites and it will throw  "Service Unavailable HTTP Error 503. The service is unavailable."

After my research (googling :) ), i found the problem is with IIS Application pool settings,and here is the solution that i have found -

Run InetMgr and open IIS Manager -

Go to  Application Pools  - Right Click -> Advance settings -> Process Model and Change the Password for the Identity.

Hope this information is helpful for someone.