Microsoft Outlook allows you to configure options for how read receipt requests are handled. When you receive an email for which the sender has requested a read receipt you can configure Outlook to ignore the read receipt request, always automatically send a read receipt or ask you email by email whether to respond with a receipt or not.
To configure the read receipt options, choose the Options option in the Tools menu.
The, in the Outlook Options dialog, choose the Email Options … button near the top of the Preferences tab.
Finally, in the Tracking Options dialog, choose the desired option before pressing the OK button.
For more Outlook tips, see Configuring the Default Email Account in Microsoft Outlook.