VS2010 MFC class wizard not generating files

Hi,

I am attempting to use the MFC class wizard to create the class associated with a CDialog.

I right click on the dialog, select "add class", the "MFC Add Class Wizard" opens like always..

I set the Class name.. I change the base class to CDialog.. I press finish.. but the .h and .cpp files never get created.

I've done this before and on this same project.

I'm curious what I've messed up or am doing wrong?

How can I correct it and get on with work?

Thanks

Andy