Website shows 503 internal server error: CPU time for application pool has been throttled

Symptoms

• Website inaccessible:

  CONFIG_TEXT: 503 Service Unavailable

• Application Pool and the website are running

• The following error can be found in Event Viewer:

  CONFIG_TEXT: CPU time for application pool 'example.com(domain)(4.0)(pool)' has been throttled.

Cause

Application Pool misconfiguration.

Resolution

1. Connect to Plesk server using RDP .

2. Open IIS(Internet Information Services): click Start > Run... , type inetmgr and press OK

3. Navigate to IIS > SERVER_NAME > Application Pools

4. Right click on the appropriate Application Pool and click Advanced Settings
   
   

5. Set the Limit to 0 and Limit Action value to NoAction .
   

Additional information

How to monitor and manage CPU usage for domains in Plesk for Windows