When using a portable system away from the domain network the Outlook integration may not allow users to view their archive and only display the login box with all settings grayed out.
When using GPO to manage Visible-Archive the options for the Outlook Add-In are disabled as they are set by policy. However "Integrated Authentication" only works while users have an active connection to their domain. The add-in is not able to access the users cached credentials. To resolve the users GPO should be updated to allow for "Standard Authentication" allowing the user to submit their archive credentials.
This problem only affects on-premise users of MailStore.