KeyError: 'main_template'
This Error Reference applies to:
Plone 3.0.x, Plone 2.5.x
This Error Reference is intended for:
Any audience.
Check portal_skins to see if your product's generic setup profile (specifically skins.xml) has removed all the skin layers except the one(s) provided by your product. One example of how this might happen is if the "based-on" value in the <skin-path> declaration in skins.xml refers to a theme that does not exist.