The web says: Covers one person and allows activation on up to 5 personally owned computers

This seems like a counter-productive and useless limitation. Most users don't share their email account with others but many have more than 5 devices. For an email scheme to be usable it must be available to the user whenever and wherever they are. I, for example have about 12 devices. I don't often use more than one at a time but I would NEVER adopt an email scheme that required me to be using a specific, license computer to get mail.

It seems to me that the only thing that a scheme like this protects against is widespread adoption. Apple doesn't impose restrictions like this; they even have family sharing. MS doesn't. Only a few dinosaurs like adobe do this sort of thing.

I was linked to your site from libre office which, of course, has no limitations whatever. I will let them know that I think it's inappropriate for an open-source app to offer links to stuff with these kind of restrictions.

Anyway, don't ecpect to see me as a customer any time soon.

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Are you using any other Mail.app plugins?