Connecting Tasklist SharePoint to Outlook 2010 - missing entries which are created before connecting List

Hi,

i have a Problem with the connection of a standard Tasklist from SharePoint 2013 to Outlook 2010. The entries which are created before i connect the list with outlook are not shown in outlook. Only the newer entries are shown. Is this a bug in SharePoint 2013 because in 2010 i can´t recognize this effect.