When opening Web Applications, "503 Service Unavailable" error is displayed.
Power Monitoring Expert 9.0
A potential cause for this error is when an application or a process is using port 80 (HTTP) or port 443 (HTTPS). This results in the Default Website in IIS being stopped, and when starting it manually the following error is prompted.
1. following netstat commands can be used in command prompt to retrieve the Process ID (PID) of the application/process that is using port 80 or 443. In this example, the PID of the process that is using port 80 is 5484
netstat -aon | find ":80"
netstat -aon | find ":443"
2. The result will be something like the below:
In this example, the PID of the process that is using port 80 is 5484.
3. The process associated with this PID can be found in Task Manager, Details tab (can be ordered by PID). In this example, this PID belongs to Skype.
4. Once the process/application is identified, (if possible) it can be temporarily ended from Task Manager (right-clicking and selecting End Task), to examine if the Default Website in IIS Manager can now be successfully started which then results in Web Applications to return to normal operation. If this is the case the identified application (in this example Skype) needs to be configured to deploy another port.