Pro needs an active licence to get updates. The key is in the email you get after buying, and in My account.
- Install and activate the free NHR Database Cleaner from Plugins › Add New.
- Download the Pro zip from My account and upload it in Plugins › Add New › Upload Plugin, then activate it.
- Open Tools › Database Cleaner › Licence, paste the key and choose Activate.
If it says the limit is reached
Each licence covers a number of sites. Remove a site you no longer use in My account, then activate again.
When a yearly licence ends
Pro keeps working. Updates and support stop until you renew.