Message recall in Microsoft Outlook

From espinola.net

Message recall in Microsoft Outlook only works under very certain circumstances, and it rarely works how you would expect or want it to. Any message recall attempts will be obvious to the original recipient, as there will be a special email in their inbox indicating the attempt, and they will be asked yes/no if they wish to allow the recall attempt.

Many people ask how message recall works, but this question is best answered in in terms of how or why it doesn't work:

Reasons why "Recall This Message..." doesn't always work

1. The recipient mailbox you are trying to recall the message from is not on an Exchange Server. While message recall may work in a local Exchange server, it very likely will not work for any emails sent outside of that Exchange organization. The intended environment for message recall is an Outlook client with an Exchange server.
2. The message expired. The message is no longer considered new because the user has read it or something has touched and altered the message in a way to make it no longer appear new. This can be caused by messages being moved from the inbox into a subfolder while the user is not actively connected to their mailbox (a server-side inbox rule).
3. The recipient is not currently logged into Outlook. The recall action runs like a client-side inbox rule, so the user must be connected to their mailbox in order for the message to be recalled from them because they need to have read the recall notification and either accepted it or refuse it.
4. The recipient refused the recall request. The recipient is given the choice to accept or deny the recall based on a special recall notification received as an email message. The recipient is free to refuse the request.

I don't recommend that message recall is attempted to be used at all. The risk of it not working is unpredictable because of the reasons outlined above -- and the potential for causing an awkward situation regarding why you are attempting the message recall is too great. Instead, send a follow-up e-mail explaining why you would have preferred the message not to have been sent -- or explain any corrections and addendums that need to be made to the original.