OLEXP: Replying to a Message May Not Use the Account It Was Received In

If you receive a message on an account that is not your default account and then reply to the message by pressing ALT+S or clicking the Send button, the message is not sent from the same account on which it was received. The message may be returned to you as undeliverable.

This behavior occurs because pressing ALT+S or clicking Send causes the message to be sent from your default mail account. If the message is received from an Internet mail server but your default account is set for an intranet server, the message is not delivered to the original sender because the sender is not found on the intranet server.

To send a reply message using the account on which the original message was received, click Send Message Using on the File menu, and then click the appropriate account.

Microsoft has confirmed this to be a problem in Microsoft Outlook Express 4.0. We are researching this problem and will post new information here in the Microsoft Knowledge Base as it becomes available.