Microsoft Exchange Client Keeps Unsent Mail in Outbox

If you quit Microsoft Exchange with unsent mail in the Outbox, you receive the following message: This behavior is not the same as in previous versions of Microsoft Mail products. Previous versions offer you the option of sending unsent mail in the Outbox before the program closes.

Microsoft Exchange does not offer an option to send unsent mail when you quit the program because of the complexity of simultaneous, multiple service providers. This avoids the possible launch of asynchronous dial-up sessions with service providers during exit.

You can force mail in the Outbox to be sent before you quit Microsoft Exchange by clicking Deliver Mail Now on the Tools menu.

If you click Save on the File menu, or if you reopen the message and then close it, the message becomes inactive. You need to open the message and send it again.