.net - Visual Studio Enterprise Library Configuration Addon throws an error -

hi seem having problems enterprise library config extension visual studio 2012.the first time installed worked fine , managed finish configurations needed.

but when try open error:

now have checked if installed , points correct paths in project csproj , should ok.

i have installed enterprise library version 6.

i have made sure enterprise library configuration addon version 6.

is there else make work?

edit

i have tryed create new aplication test extension , seems works on new application.it seems related curent solution.anyone have ideeas why?