Resolving Service Unavailable 503 Issue In SharePoint Server 2016

In this article, you will learn how to resolve "Service Unavailable: 503" issue in SharePoint Server 2016.

SharePoint 2016 general availability was announced in the Future Of SharePoint conference in May 2016. The series that discusses the installation of SharePoint 2016 in Azure can be found at C# Corner from the below links.

You can also read about the new features and the deprecated features in SharePoint 2016 from here. With SharePoint 2016 Mini Roles, Servers (dedicated for specific functionalities) were introduced, which was an attempt to off load the SharePoint Server from some of the functionalities.

We have 5 Mini Roles -
  • Front-end
  • Application
  • Distributed cache
  • Search
  • Custom

I had installed SharePoint 2016 as a Single Server Mini Role in Azure for testing out the new features. However, a month after the installation, one fine day, when I tried to access the SharePoint Sites, I received the infamous ‘Service Unavailable’ error.



So, I tried checking the Central Administration site to see if it was working.



To my surprise, it had gone down as well. The entire SharePoint service has gone down.



This seemed to be a farm wide issue and I was left without many options. Then, I had to start debugging in order to find the root cause of the issue. First thing to check was to ensure if all the Services related to SharePoint and MS SQL Server were up and running.

 So, I had to go to Services.msc.

As suspected, the SharePoint Timer Service is in stopped state for some reason. So, I tried to start the timer by clicking on Start.



Another setback, the timer service did not start due to a logon failure.



So, the whole error boiled down to the user account issue. I checked the user account under which the SharePoint Timer Service was running.


The most probable reason for the logon failure is the user account under which the service was running could have had a password reset/expiry. Let's head over to the IIS Application pools and see if they are running.


The application pools also have gone to the stopped state.



The identity under which they were running definitely had a password expiry/reset. Let’s go to the advanced settings option where we can update the password for the user.



Click on the highlighted button.



Specify the password for the User account and update the password.



Now, try to start the application pool.



This time, the application pool for the web application has started. Now, do the same for the Central Administration Web application pool, as well.



Now, both the web applications have their identity updated and have been started.



Let’s head over to the SharePoint Central Administration. This time the site has come up.



The SharePoint Sites have also started working.



Summary - Thus, we saw how to resolve the ‘Service Unavailable: 503’ issue in SharePoint Server 2016