the user with Outlook Express would need to install Outlook and switch to it as their email client.
A possible work-a-round would be to to make use of tracking receipts to see when a message was read. That would allow you to send a reminder shortly before the event (which you actually could do anyway). The read receipt is only good though if the OE user hasn't disabled read receipts.
If you really want or need a feature you MUST use the software that supports the feature on both ends.
Love the calendar feature that allows me to schedule appointments in M. Outlook 2003. They pop up regularly and I must dismiss or snooze them. They don't simply go to email where I can forget about them, I have to act.
But when I invite an attendee who has XP and Outlook Express all he gets is an email message, so he can forget. I'd like him to get the pop-ups too. Possible?

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