Symptoms
Trying to open Parallels Plesk Panel in browser you receive "HTTP Error 503. The service is unavailable".Parallels Plesk Panel uses IIS as Web server.
IIS Advanced Logging or IIS Mod-Rewrite is installed on the server.
Cause
Plesk Default application pool crashes in several seconds after restart with errors like:Log Name: System
Source: Microsoft-Windows-WAS
Date: 9/29/2009 1:02:52 PM
Event ID: 5139
Task Category: None
Level: Warning
Keywords: Classic
User: N/A
Computer: Test
Description:
A listener channel for protocol 'http' in worker process '3768' serving application pool 'PleskControlPanel' reported a listener channel failure. The data field contains the error number.
This is caused by the IIS Advanced Logging or IIS Mod-Rewrite feature installed on the server which makes custom additions to the Default application pool workflow.
To be exact in case of IIS Advanced Logging the C:\Program Files\IIS\Advanced Logging\AdvancedLoggingModule.dll is called while Parallels Plesk Panel is unable to configure IIS workers to handle it properly. In case of IIS Mod-Rewrite the same happens with C:\Program Files\Micronovae\Mod-Rewrite\Modules\v3.5.3\imodrewlib.dll.
Resolution
Add 'Modify' permission for 'psaadm' user on the folder containing aforementioned modules (the path may differ slightly depending on your system settings):C:\Program Files\IIS\
C:\Program Files\Micronovae\Mod-Rewrite\
and restart Plesk Default application pool in IIS.