What happens if I send an instant message to a friend who appears to be offline?
If your friend is actually offline, your instant message will received as an offline message. The offline message will be displayed to the friend the next time he/ she comes online.
If your friend has signed in as Invisible (and so appears offline), he/ she will receive your message instantly, which he/ she may choose to reply to or ignore. Of course, there is no way to tell whether a friend is actually offline or merely signed in as invisible.
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