Windows 10 Pro, Outlook 2016. I have a correspondent in Austria, let's call her Joan Smith (not her real name). Her E-mail address is "email@example.com". In my address book she is listed as "Joan Smith <firstname.lastname@example.org>". When I want to send her a message, I can type a "j" (upper or lower case) in the address space, which gives a dropdown menu with "j" names including "Joan Smith <email@example.com>". When she replies to me, the return address is listed as "firstname.lastname@example.org" without the "Joan Smith" part. If i incautiously reply to such a message "as is" without first hitting the "j" and selecting the full name and address to replace what's in the address space, the message goes out to "email@example.com" without any name, and my automatic popup entry of "Joan Smith <firstname.lastname@example.org>" is gone forever. To get it back I have to delete the "email@example.com" from the dropdown list, reboot the computer, open up Outlook, write a new message to "Joan Smith <firstname.lastname@example.org>" and send it, reboot the computer again, and only then when I hit "j" in the address space "Joan Smith <email@example.com>" will appear among the "j" choices in the dropdown menu.
Can anybody tell me what I have to do to avoid having her "name-less" return address override the entry in my automatic search list? Set the search to use the address book instead of the automatic search list? My address book has about 2500 entries, at least 50 of them under "j", so the resulting dropdown would be much more unwieldy than the automatic one which includes only those people with whom I actively correspond.