Supported accounts. To use this feature, you need an Office 365 work or school account, or an Exchange on-premises account. Select Tools > Accounts to check your account type.
Unsupported accounts. This feature isn't available for Outlook.com accounts, or for IMAP or POP accounts such as Gmail, Yahoo!, or iCloud.
Request a read receipt
4. Send your email.
Note: Tracking doesn’t appear until at least one receipt has been received. After you receive the first receipt in your Inbox, it might take several minutes before the Tracking button is available.