There are volumes to be had about e-mail etiquette, or the manners and rules surrounding the sending and receiving of electronic missives. The bottom line is that you don’t want to accidentally tick someone off. So how can you tread that invisible line?

I received an e-mail question on this topic recently. Here’s the gist of it:

When I send a message to a group and only one person answers, can I respond to the entire group by hitting the “Reply” button, the “Reply to All” button, or do I have to go to the To: box and specify the group each time?

Whether you use Reply or Reply All depends on how the message was sent by the recipient, not how they received it. So you really don’t have any control.

For example, say you send a message to four people. You get a reply from one of the people.

If the person replying just clicked the Reply button, then the reply is sent only to you. Whether you hit Reply or Reply All, your response goes only to that one person.

If they hit Reply All, then the reply is again sent to everyone. If you hit Reply All, your response is sent to everyone again.

But on the larger picture, there comes the issue of e-mail etiquette: When someone replies directly to you, and then you include other people in the reply, then you could be violating one of the unwritten rules of polite e-mail. That rule:

Keep private messages private.

When someone sends you a reply and then you forward it or CC the reply to others, that’s considered bad form. Without asking permission first, you may make that person angry with you for sharing what they considered to be private correspondence.

It is allowable to share the information anonymously: Copy the message text only. Then paste that text into a new message you send to others. That way you keep the original e-mail and the sender’s identity confident. I often do this when I forward a question from a reader to my publisher; I cut out their personal information and include only the relevant part of the message.

To (finally) answer the question, to reply and ensure that everyone is included, you must manually add the group. Just be certain that it’s okay to do so. You can ask, “Is it okay if I forward this message along to my study group?” If they don’t reply or say, “No,” then don’t do it.

The world of e-mail etiquette is vague. But one rule is certain: There is no Un-Send button.

Speaking of Which Dept. E-mail etiquette rules at emailreplies.com. E-mail etiquette form Cornel University.