Because development has ceased, Postbox users are eligible for exclusive discounts to switch to Full Credit

It sounds obvious, but the single best source for an exclusive code is Postbox itself. The developers occasionally send out "loyalty codes" or "upgrade discounts" to subscribers.

If you travel, you can use your exclusive code to manage your mail from anywhere in the world. You can direct mail to be scanned, forwarded, or shredded via an app, and only use your physical code when necessary [1]. 4. Professionalism for Businesses

: While a standard Postbox license covered multiple personal machines, eM Client's personal license traditionally supports fewer concurrent devices.