Question about Outlook Express

I am a developer for IMVU Inc. Normally I receive sales notifications from IMVU quite frequently daily. However, now it seems they are automatically being put into a folder (indicated by a double folder icon) as one mail. When I try to click it I get the error that I am unable to connect to Hotmail services at this time. Did I accidentally click something that may have marked the sender so that it will perform this way? Or is there a limit to the number of mails a contact can send you thus forcing them into a folder? At any rate, any help would be much appreciated. Thank you.