Sometimes you get the following error when accessing DBWebadmin (phpMyadmin ) in plesk
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#1045 - Access denied for user ‘pma_tUuzljY3KmgS’@’localhost’ (using password: YES)
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pma_tUuzljY3KmgS may vary according to your system
To fix this
vi /usr/local/psa/admin/htdocs/domains/databases/phpMyAdmin/libraries/config.default.php
and change the values of controluser , controlpass , pmadb to null
thats it ;save the file and now everything should work fine
Ref: http://forum.swsoft.com/showthread.php?s=&postid=167179#post167179

You can use third party programs like qmail-remove http://www.linuxmagic.com/opensource/qmail/qmail-remove to accomplish queue management in plesk control panel managed qmail
The Plesk control panel itself provides a modified version od qmHandle ( http://qmhandle.sourceforge.net/ )along with it that can be used with ease to manage the queue
To see the statistics of the queue:
–
/usr/local/psa/admin/bin/mailqueuemng -s
Messages in local queue:  0
Messages [...]

This script is useful in extracting the Parallels Plesk control panel client/reseller login ,password and email address.An quick script to aid in troubleshooting plesk login problems
wget http://gnusys.net/downloads/psaclientpass.bash
bash psaclientpass.bash

This script comes handy to anyone who wants to extract the passwords for ftp users for a plesk domain.
OfCourse the username can be obtained from the Plesk control panel
The script also retrieves the home directory to which the user logs in when he authenticates successfully to the ftp daemon
wget http://gnusys.net/downloads/psaftppass.bash
bash  psaftppass.bash

The following script is very useful if you are planning to migrate or sync all database of a paticular reseller.I made it to aid in database recovery of a client from a failed Plesk Migration Manager (PMM) migration
Script has been tested to work on Parallels Plesk upto version 8.3.The output of the script is self [...]

You can change the php memory_limit value for a particular domain or on a per virtual host basis by the following way
Add the following line to the file
/home/httpd/vhosts/gnusys.net/conf/vhost.conf
php_admin_value memory_limit “128M”
Reconfigure the vhost by running the following command
/usr/local/psa/admin/sbin/websrvmng –reconfigure-vhost –vhost-name=gnusys.net
and restart the webserver using the command
/usr/local/psa/admin/sbin/websrvmng –restart
Check if the setting is correct using phpinfo(); function

The following script retrieves the password of a mailname given the mail account name as input
This is version.2.0 of the same .The previous one i had written was very complex and created many files in /tmp which was useless.Version 2.0 is an elegant approach and will not create any stale files!
wget http://gnusys.net/downloads/psamailpass.bash
bash psamailpass.bash