I think the error occurs because the run as information is missing and the tasks is corrupted. I was not able to find anything on the forums at Plesk for this error. My only fixed was to delete and recreate the tasks. Oh yeah there is one more problem , i was not able to view the properties for the tasks so i could not see the commands. I add to pull the commands from another working system. i have posted the commands below aliong with the task name. This worked on Plesk version 8.3
All the start in folders should be “C:\Program Files\SWsoft\Plesk\admin” and write down your current schedule for the task and reenter it. The task can run as the system user or the admin .
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Task :
Plesk Scheduler Task #{0C235029-C1F5-4916-AB08-1C6FEA9CE9EA}
Command to execute

C:\WINDOWS\system32\cmd.exe /c “”C:\Program Files\SWsoft\Plesk\admin\bin\runtask.exe” “–application=C:\Program Files\SWsoft\Plesk\admin\bin\php.exe” “–parameters=-q -dauto_prepend_file=\”\” -c php.ini \”C:\Program Files\SWsoft\Plesk\admin\plib\report\autoreport.php\” –auto daily”"

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Task :
Plesk Scheduler Task #{7F9CD2FC-8C81-4f3c-AE0B-BB8C9BA560A7}

Command

C:\WINDOWS\system32\cmd.exe /c “”C:\Program Files\SWsoft\Plesk\admin\bin\runtask.exe” “–application=C:\Program Files\SWsoft\Plesk\admin\bin\php.exe” “–parameters=-q -dauto_prepend_file=\”\” -c php.ini \”C:\Program Files\SWsoft\Plesk\admin\plib\report\autoreport.php\” –auto monthly”"

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Task

Plesk Scheduler Task #{99254CDC-8EA7-49ee-8A49-FC2A169843B7}

Command
C:\WINDOWS\system32\cmd.exe /c “”C:\Program Files\SWsoft\Plesk\admin\bin\runtask.exe” “–application=C:\Program Files\SWsoft\Plesk\admin\bin\php.exe” “–parameters=-q -dauto_prepend_file=\”\” -c php.ini \”C:\Program Files\SWsoft\Plesk\admin\plib\report\autoreport.php\” –auto weekly”"
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Task name – stats command
Plesk Scheduler Task #ad08f1e5-f9e2-4be7-b4f7-fc8248acf5e8

command
C:\WINDOWS\system32\cmd.exe /c “”C:\Program Files\SWsoft\Plesk\admin\bin\runtask.exe” –defaultmail “–application=C:\Program Files\SWsoft\Plesk\admin\bin\statistics.exe” “–parameters=”"
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Task
Plesk Scheduler Task #C6586631-C086-43FE-9B96-BA28E52FDCD6
Command
C:\WINDOWS\system32\cmd.exe /c “”C:\Program Files\SWsoft\Plesk\admin\bin\runtask.exe” “–application=\”C:\Program Files\SWsoft\Plesk\DrWeb\drwebupw.exe\”" “–parameters= /GO /ST \”/RPC:\Program Files\SWsoft\Plesk\DrWeb\DrWebUpW.log\” \”/DIR:C:\Program Files\SWsoft\Plesk\DrWeb\\\”"”

or trying using the ip address as such

http://ipaddress/_vti_bin/_vti_adm/fpadmdll.dll?page=webadmin.htm

always create the fp user within fp admin and not under computer management

server admin

http://ipaddress:7814/fpadmdll.dll?page=fpadmin.htm

the port can be something different depending on the server

Here is how you can access the IP Address Management page where you can add and remove IP addresses, refresh the list of IP addresses, and edit the IP address properties:

1. Login to your Plesk Control Panel using admin as “Login” and your dedicated server password as “Password”.

2. Click on Server from the navigation bar on the left.

3. Click the IP Addresses icon.

4. You will now see the list of available IP Addresses on the server.

Here is how to set the default domain for a particular IP Address:

1. At the IP Address Management page, click the number in the Hosting column of the IP Address you’d like to manage.
2. Select a domain from the list using the respective radio button.

3. Finally, click the Set as Default link.

the solution is in proper host headers (duh) assuming as most of you are running multiple web sites/ip.
Make sure the ‘Default’ pointer is set to the correct port and the host header value is ‘blank’. Mine got screwy trying different ports.
I am also running SM on iis port 9998 & ‘All Unassigned’ now (same as SM server default). Although you can probably choose any port.

incompleted

In Plesk each domain has virtual hosts configuration stored in a separate file:

/home/httpd/vhosts/<domain-name>/conf/httpd.include

This file is overwritten each time the virtual host configuration is changed, thus any manual alterations made to the file are discarded. To use custom directives or redefine those inserted by Plesk, you need to create the files vhost.conf and/or vhost_ssl.conf with necessary directives in the directory /home/httpd/vhosts/<domain-name>/conf/

If any (or both) of these files exist by the time the main configuration file is generated, Plesk inserts the appropriate directive Include /home/httpd/vhosts/<domain-name>/conf/vhost.conf or Include /home/httpd/vhosts/<domain-name>/conf/vhost_ssl.conf into the HTTP and/or HTTPS virtual host context respectively.

For security reasons, only root can create the vhost.conf and vhost_ssl.conf files.

For the changes to take effect, you need to run the following: or restart httpd

/usr/local/psa/admin/sbin/websrvmng --reconfigure-vhost --vhost-name=<domain_name>

or windows
In Windows command prompt:
Code:

cd c:\Program Files\SWSoft\Plesk\admin\bin
websrvmng –reconfigure-vhost –vhost-name=domain.com

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changing stored procs

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