Unable to load cad document templates

Hi,

I am unable to load cad document templates due to following error : The type 'WCTYPE|wt.epm.EPMDocument|................' cannot be imported into this system. Its name '......' has been used by other type 'WCTYPE|wt.epm.EPMDocument|.......' Error loading data from file.

Please let me know if any one has any solution for it.

Thanks

Senthil