How To Remove Members folder from Navigation bar

The simplest way to move things from navigation bar is to click properties of a folder and tick the box exclude from navigation bar. However for Plone 2.1.1 we found doing this for Members folder deleted the whole navigation bar. Hopefully this will be resolved in a future version of Plone.

Another fix that can be used is

 
The second method is to visit the portal_properties/navtree_properties object and add any desired items to the idsNotToList property. This removes the item form the portal tabs but may also remove it from the navigation - which may or may not be desired.

The third method is to set the "Exclude from navigation" checkbox to True (Checked) in the Properties tab of the plone site for the object in question

(Thanks Medur)