#Exchange2010 #Outlook #Exchange … Interesting
Source: http://support.microsoft.com/default.aspx?scid=kb;EN-US;2540817
After an Exchange Client Access Server (CAS) is restarted, the Microsoft Office Outlook 2007 client prompts you to re-enter your credentials to reconnect to the Microsoft Exchange server. (This behavior is not experienced if you are connected to the Exchange CAS server by using Outlook 2010.)
To work around this issue, follow these steps to enable the DisableTransientFailureAuthPrompts