# How to mention someone in comments if his\her name doesn't appear after typing its first letters?

Suppose there is a question of a member $A$. I want to mention this member $A$(so it appears in the comment as "@A"). sometimes,when I type the first letters of name "$A$", The name appears in a rectangle above and I click on the name so the member is mentioned. Many times, When I type the first letters , no thing happens!

What to do in this case? Can I mention him\her manually? How to do this? Suppose that his\her name was "$A\text{ } B$"(there is a space, like in "Maths Lover"). Should I type "@MathsLover" or "@Maths Lover"

Added: When I try to mention the member manually, his name disappear when I post my comment. How to deal with that?

## 1 Answer

When you comment under a post, the post author is always notified, so there is no need to alert her/him with an @-ping. If so far nobody except you and the post author have participated in the comment thread, an @author is automatically removed from the comment, since it is deemed clear whom you address with your comment. If you nevertheless want to explicitly address the post author, do that without an @. If other people have posted comments on the post, an @author is still not necessary to notify the author, but will not be removed, since it is now not a priori clear to whom your comment is addressed.

Explanation of replies on Meta.SE

• Ok, but If there is no one participated in the post but me and the author. When I add a comment(like what I'm doing now) Does the author of the post reciece a notification that someone commented in his answer? – Fawzy Hegab Aug 21 '14 at 13:08
• Yes, the post author is always notified of comments on their posts, whether they contain an @-ping or not, and whether they are addressed at somebody else or not. (Unless the notification system is broken, which occasionally happens for some time.) – Daniel Fischer Aug 21 '14 at 13:10
• And why is the notification system is broken from time to time? Is there is a technical problem? Why not to find a permanent solution to it? – Fawzy Hegab Aug 21 '14 at 13:19
• Last weekend, the failover test caused the notification system to be broken (but, as far as I'm aware, not in a way that notifications weren't delivered, but that already read notifications popped up again after refreshing the page/opening a new page; no idea what caused that). Every umpteen years, somebody codes a bug in the newest build, and things are broken until the next build is rolled out (typically rather soon after the bug was detected). By and large, things work, but on rare occasions, they break, as everywhere. – Daniel Fischer Aug 21 '14 at 13:28