Windows Phone - Exchange Mailbox does not appear when a contact is saved

Hi,

I have two mailbox with a problem, the users erase the default Contact Folder in their Outlook; they have other Contact Folders.

Windows phone sync correctly all Contact Folders, but when they want save a new contact these are not visible.

I think that default Contact Folder have an special attribute like "principal sync", and the new Contact Folders don't have it.