I run a Microsoft IIS server that hosts a student application. When it was installed by a third party vendor, I gave them a specific username and password that was a Domain Admin on our Active Directory network. They installed various application pools and other items under this username.
Once they were finished and everything was up and running, I disabled that account. Little did I know, they had installed an application pool with these credentials. So once I rebooted the server, the application pool did not start and I received a HTTP Error 503 – The service is unavailable error code.
Once I found the application pool, I performed the following:
- Open IIS Manager
- Click on the Application Pools option in the left menu
- Found the application pool that was stopped, right mouse clicked and chose Advanced Settings
- Under the Process Model section, under the identity option, I clicked the “…” button and then clicked on the SET button. I then entered the correct username and password.
Once this was done, I right clicked the application pool and selected START. It started immediately and the 503 error was no longer a problem. Yay!