- Take Outlook Offline. Go to the Send/Receive tab, click “Work Offline”, and wait for this to be reported in the connection area in the lower-right corner.
- Compose a new email. Include in its “To:” field, the entire contents of “Suggested Contacts” and address books and anything else which should be included.
- Send the email. Because Outlook is Offline, it won’t be sent, but AutoComplete will be repopulated.
- Delete the email from your Outbox!!!
- Take Outlook Online again.