# Plesk get_key_by_product() error

Posted on April 23, 2011

Error: Plesk 9.x for Windows Fatal error: Call to undefined function of_get_key_by_product() in C:\Program Files\Parallels\Plesk\admin\plib\common_func.php3 on line 4501

Solution: The error is being caused by the registry.xml being empty zero bytes. The file is normally located in C:\Program Files\Parallels\Plesk\admin\repository

Pretty much what you need to do is remove this file and then restart Plesk.