When I send an email, I type two or three letters and select the recipient's full name in the list that pops up. A great feature. But one day I mistyped an email address and now have several junk entries in that list. How do I delete those?
Go ahead and complete that "bad" name, then click on the downward arrow to the right of the address.
You can also use the Previous Recipients window to clean things systematically rather than on demand when you are composing and seeing the ones you wish to prune. Once that is complete, check your contacts to make sure the bad address is not stored as a legitimate contact.