Question

How to fix HTTP error 503 The service is unavailable IIS?

I’m facing an HTTP error 503: 'The service is unavailable' in IIS. Can someone guide me on the possible causes and steps to fix this issue?

Answer 1

To solve the error, follow these steps:

1.Check IIS Application Pool:

Open IIS Manager.

Navigate to Application Pools.

Ensure the relevant application pool (e.g., SharePoint - 80 or Central Administration site) is running. If it's stopped, start it.

2.Verify Application Pool Identity:

In IIS Manager, check the Identity of the application pool in question.

Ensure the identity has the necessary permissions and is part of the IIS_IUSRS group.

3.Review Services:

Open Services.msc.

Confirm that services like World Wide Web Publishing Service and other related IIS services are running.

4.Check Local Group Policy:

Use gpedit.msc to verify that IIS_IUSRS is included in the Log on as a batch job and Impersonate a client after authentication policies.

5.Analyze Logs:

Review the Unified Logging System (ULS) log files for clues. These logs are located in:

C:\Program Files\Common Files\microsoft shared\Web Server Extensions\16\LOGS