What OS? Are they logging into a network?
FWIW, I get the same dialog with SPS subscribed calendars and the remember
password option doesn't remember the password. It's a network authentication
problem - I'm not logged into that network.

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Diane Poremsky [MVP - Outlook]
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> We are using the calendar subscription through Outlook 2007 to share
> calendars. For the most part it works fine. But now we have a couple of
[quoted text clipped - 3 lines]
>
> Thanks.