error 404 for menu item "My Assigned Post layout"

hi StackIdeas,

I have added to my menu an item of the type "My Assigned Post layout" (index.php?option=com_easydiscuss&view=assigned). But calling this menu item throw on my website error 404. Other menu type option displaying all discussions (index.php?option=com_easydiscuss&view=index) works fine. I could not find any reason of this problem. Would you have any hints for me?

thanks a lot in advance
Martin