Mac hints and tips
Use email read receipts in Mail
When you create an email message in Mail and click the Send button in the toolbar the message is then sent to the recpient's address that you entered into the to box. Email messages are delivered extremely quickly and they often appear to be almost instantaneous, well, unless you add a huge attachment that is.
We tend to assume that email messages always arrive safely, but this isn't always true and there are many obstacles in the way that may prevent them from being delivered. For example, a message may be mistaken for spam by software on the recipient's computer and automatically deleted or filed along with dozens or even hundreds of other spam messages where it will never be found.
Anti spam systems on the internet by email service providers may block your message before it even reaches the recpient. Computer glitches, communications errors and other problems may prevent the message from being delivered too.
So how can you tell whether an important email messsage has been read by the recipient? (It's no use just ensuring it is delivered, because it may be redirected to a spam folder and never read). One way to do this is to use a read receipt.
An email message has a header that contains lots of imformation, such as who it is to, who it is from and so on. An optional extra bit of information that can be included in the header is a request for a read receipt. When the recipient reads the email message on their computer the email software will automatically send an email back to the sender stating that the recepient has read the message and it includes the time and date it took place.
It is a very useful facility because if you receive an email receipt in your inbox you can be sure that the person you sent the email to has definitely read the message that you sent to them. However, it is essential that you realise that if you request an email receipt when you send a message, but you don't receive that all-important receipt, it does not mean that the person has not received and read your message.
Read receipts are an optional part of email messaging and the recipient may not be using software that recognises read receipt requests. If their email client does handle read reaceipts it won't automatically send them unless it is specifically configured to do so. The user will probably see a pop-up message box that asks for their permission to send a read receipt when they read the email. The user has to click Yes in order for it to be sent. This means that the recipient has to be cooperative and actively choose to send a read receipt, but it is still a very useful feature to have occasionally.
OK, you're convinced that read receipts are useful, how do we request one in the Mail application? Actually, there isn't a command, menu, function or option to request a read receipt in Mail. That might seem to be the end of the matter, but there is a way around the problem.
Open a Finder window and go to your home folder. Open the Library folder and then Preferences. Double click com.apple.mail.plist to open it in the Property List Editor. This file is used by Mail to store all its configuration settings. Expand the Root entry to see them. With Root selected at the top, click the New Child button and name it UserHeaders. Select UserHeaders and click the arrows next to String in the Class column and set it to Dictionary.
With UserHeaders selected, click the little triangle next to the name so that it points down. You can then click the New Child button at the top of the window. Name it Disposition-Notification-To, then click in the value column and enter your email address. With this new item selected, click the New Sibling button again and name the item Return-Receipt-To. Click in the Value column and enter your email address. Click File, Save and then quit the property list editor.
What you have done is to add two user-defined headers to be added to email messages. When Mail creates a new email these two extra header items will be automatically included and the recipient will be requested to send a read receipt for any email messages they receive from you. Note that all messages you send will request for a read receipt there isn't a simple way to turn read receipt requests off or back on again. Tio turn off read receipts, open com.apple.mail.plist in the Property List Editor again and delete your email address from the two values you created - Disposition-Notification-To and Return-Receipt-To.
Finally, let's look at an alternative way to add the read receipt setting to Mail's plist file for advanced users. All you need to do is to open a Terminal window and enter the following command:
You can save having to type this in by selecting it above, copying it, and then pasting it in to the Terminal window at the command prompt. Change [email protected] to your pwn email address, obviously.