1. Select Exchange from the list of email service providers in your iPhone's Settings-> Accounts & Passwords-> Add Account.
2. Fill up your company's email address. You may also give your email account a description if you wish.
3. To connect to your Exchange Server, choose either Manual Configuration or Sign In. If you wish to manually set up and configure your email account, choose the first option; otherwise, choose the second option. If you want to manually configure your account, you'll need to fill in the server settings for incoming and outgoing servers, as well as port numbers and other details.If you don't know what server settings to use, contact your system administrator. If you don't want to sign in, use the option to automatically connect to your Exchange Server. If you select Sign In, Microsoft will use your email address to discover and validate your Exchange account information. If your account requires multi-factor authentication, follow the special authentication procedure that will be supplied.
4. Mail, Contacts, Calendars, Reminders, and Notes may all be synced.
5. Finally, press Save to finish the email configuration procedure.
6. You may update your Exchange email account settings at any time by navigating to Settings-> Accounts & Passwords-> Exchange email account.

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