While trying to delete a registered File Server/SQL server you might receive an error below.
Error in deleting Server. Error: “Unable to Delete Device because it is currently linked to a SQL product."
This is because we have a backup set associated with it.
1) Using web browser login to Phoenix console.
2) From the Dashboard. Navigate to > Protect > MS-SQL Server > Click on the SQLSERVERNAME > SQL Backup Set
3) Delete the respective backup set which belongs to that server.
Deletion operation is an irreversible action. Please delete only if this is not required
4) Then try to delete the server from the console.