Please note that changing this does not change existing contacts, it applies only to new contacts. Restart Outlook to insure changes made here to take effect. Changing this setting will not change existing contacts, it applies only to new contacts. When Outlook files names in 'Mary, Smith' format, check your default name order setting. If you prefer to enter names in last name first name format, without using commas ('Smith Mary'), this is the setting you'll need to change. The default name order tells Outlook that 'Mary Smith' is in first name last name format. In Outlook 2010, this dialog is at File, Options, Contacts.

In Tools, Options, Contact Options you can control the file as format and the default name order.

If you maintain one contacts folder for all accounts, the Custom order is best, but it can be confusing if you have separate address books for each account type. You can choose to start with the Global Address list (Exchange server accounts only), the Contacts folder, or Custom order. This is the dialog in Outlook 2007 and older: The dialog is slightly changed in Outlook 2010 and newer, due to the new feature where Outlook chooses the sending account based on the folders you are viewing. In the Address Book's ( Ctrl+Shift+B) Tools, Options dialog, you'll find the options to select which address book is shown first when you click To, where your personal addresses are kept, and the order auto-resolution searches your address books. To remove the email address from the Display as/Display Name field, see Bulk Change Email Display Name Format.

Note that when you change the Address book display format used in the Name column, the new format is not displayed in the Address book until you restart Outlook.

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