If you previously purchased a license, you can recover your lost activation key through the Poikosoft Contact Page Lifetime Support:

If you're looking for a free activation key, there are a few options to consider:

do not use traditional activation keys; they are linked directly to your Microsoft account and can be installed on up to 5 PCs. www.poikosoft.com Free and Official Alternatives

Does someone with a mysterious request for the data?

Instead of looking for third-party keys, which often carry security risks, you can use: EZ CD Audio Converter Free: