Using older versions of Outlook for Mac in business environments
HERE'S SOMETHING THAT WORKS FOR ME!!!!!
Click on the To box.
It then takes you to a screen that says Add Recipients.
Below that is a box that says My Contacts.
Fill in the name of person who you want to address to.
It says Searching Contacts, and then name you entered pops up.
Hit the + sign and that name fills into the To: section.
Hit Save. **** ****(Left this step out of previous notes I sent out.)
To add another name in this field, repeat process.
To send CC or BCC, click on those boxes and do same thing.
Hope this helps. It seems to be working for me... at least for now.