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I have tried to find how to remove the email addresses to which you have sent emails in Mail. They are not in Contacts -application. Not in Settings.
I type masi.mathiasen... and I all the time get the contact which I removed from Contacts, just because I sent there one message before. Then, when he has got new email address it is annoying because I am writing his name there first and get the old one as autocomplete.
How can you remove an old email-address which Mail -application uses in OSX, which is not found in Contacts?