Why am I suddenly getting "Waiting for Printed Documentation's VBA macros to be registered?

When I try to generate Printed Documentation (either from an existing layout or a new one, and in multiple projects) in RoboHelp 9, all of a sudden I'm getting "Waiting for Printed Documentation's VBA macros to be registered" in the Output View along with a message in Word. Ultimately I get a message that Word's not responding. Then I get a message both in Word and in the Output View: "The Word VBA macro version registered is incorrect. Please reinstall Printed Documentation." I have no idea what's going on...help!