For simple undeletion, Recuva (free) may suffice. But for deep partition recovery and damaged file systems, GetDataBack Pro is widely considered superior by IT professionals.
Runtime Software provides a License Key Recovery page on their website. You’ll need to enter the email address used at purchase. They will resend the key instantly. getdataback license key
If you already own a previous version, Runtime Software offers discounted upgrades. Log into your customer account on their site to generate an upgrade key. For simple undeletion, Recuva (free) may suffice