Follow these steps:
1. (It assumes that you use SQL server not MSDE. If you use MSDE skip SQL transferring steps)
a).Backup domains in source Plesk server, using Plesk Backup (Start->All Programs->SWsoft->Plesk Backup->Select domains->Select archive location->Click Start)
b).Write down any DSN created for MSSQL if you use ODBC to connect to MSSQL
c). If database centrally managed,some additional steps needed:
--- ask admin of source server for database name, for database users, their password (this information you need to enter in target Plesk server)
c).move databases from source SQL server to target SQL server, more about how to move look here:
http://vyaskn.tripod.com/moving_sql_server.htm
2.
a).On the target Plesk server restore domain,using Plesk restore(Start->All Programs->SWsoft->Plesk Restore -Select archive to restore->Select by domains->Click Next-Ensure domain is present->Click Next->map IP to new IP on target server->Click Next)
b).Ensure keep current key selected (If your server is configured)
c). Enter MSSQL user and password
d).Click Start
e).After restore completes go to the Plesk CP->Domains->restored-domain->ODBC --- enter ODBC information targeting new SQL server (You can skip this step if DSN already presents) --- (Step assumes that you use DSN)
f).If source Plesk server uses centrally managed SQL server and the same you do follow these steps:
--- Start->Run->cmd
--- cd "%plesk_dir%\mysql\bin"
--- mysql -uadmin -padmin-password -P8306 psa
-- select * from domains where name="restored-domain-name-without-www-prefix"; (quote must present);
--- write down domain id (not mysql command)
--- select * from data_bases; (check last id)
--- insert in data_bases value('last-id+1','database-name-you-received-from-admin-of-source-Plesk-server','mssql','written-down-domain-id');
--write down db id (not mysql command)
--select * from db_users; (check last id)
--insert in db_users value ('last-id+1','db-user-name','db-user-password','written-down-db-id'); (username and password you have from source Plesk server)
Also check if this information is present you can skip above steps . It is depended from source and target Plesk versions and patches applied
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MSDE does not require any additional steps
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Restart Plesk and enjoy
John S.G.