Attachment Icon not working in Contacts folder/Public Folders

I use Outlook 2010 in my workplace.

I created a Contacts folder in Public Folders so all staff members have access to it. It is viewed in LIST view. Within each contact's file I inserted a pdf attachment (in the Notes section). After I save and close the contact's file the "Attachment" icon should automatically display the paper clip next to the contact's name on the list, but it does not. However, I noticed it DOES appear when I do this in my personal Contacts folder.

Is this a programming glitch or does this feature just not work when saving attachments in Public Folders?