Outlook should not choose contacts from itsown "memory" first ...

[emgtk]

Some people find it frustrating that Outlook does not suggest contacts
directly from the Contacts Folders as per the settings in "Address
Book"/Tools/Options/"check names from the ..."
Why does Outlook actually suggest from what seems to be his own database of
contacts recently/frequently used.
Could one turn that feture off?

 

[Russ Valentine [MVP-Outlook]]

Outlook does that because that's how you have it configured.
Just turn off autocompletion ("Suggest Names") and leave autoresolution
enabled ("Automatic Name checking").
You'll find both checkboxes in Advanced Email options...