Whenever possible, use the 20-digit key. It is the universal standard for all current ESET home and business products.
If you are looking for credentials to log into a portal or activate a product, use these methods: eset convert license key to username and password best
Don’t worry—you don't need to buy a new subscription. You just need to convert your "legacy" credentials. Here is the best way to handle this transition. Why the Change? Whenever possible, use the 20-digit key
If ESET is already installed and activated with a license key, you can retrieve the username/password from the software itself. eset convert license key to username and password best