How to disable autocomplete in Outlook
According to independent research conducted for the Egress Data Loss Prevention Report, 85% of employees are sending more emails than ever before and 80% of are using email to share sensitive data with clients and colleagues. To ensure users can be productive, Microsoft has continued to evolve Outlook to provide a richer and more integrated email experience for end users, adding functionality like autocomplete, clutter, and message access via the reading pane.