phplist Documentation: Restore process with phpMyAdmin

The restore process described here assumes you made a complete backup of your database as described in Backup your database with phpMyAdmin.

Log into phpMyAdmin on your server
From the main screen, select 'Databases'
Click the name of your PHPList database
Click on the SQL tab in the top menu bar.
Click the button labelled "Choose file".
In the resulting dialog box, select the MySQL export file (i.e. your backup file) from your computer. Leave the "Compression" option at "Autodetect" unless you experience problems.
Click on Go, and your database should be restored.

phplist Documentation : RestoreDatabase