Compile error - Buffer cannot be null?

[Claypaws]

I am new to Flare, (former RoboHelp user ). Just started a new job recently with Flare as the major tool and am mostly liking it, but still have a way to go to get up to speed. I created a new project based on a previous HTML5 Flare project in a suite of user documentation. When I "Build Primary", I get the following error message "compile error - buffer cannot be null?" Can anyone shed some light on this - or perhaps point me to a thread, knowledge base article or somesuch?

Many thanks,
Sally

[LTinker68]

I think I'd first check the target file assigned as the primary target and check all its settings to make sure it's pointing to masterpage, master page, stylesheets, etc., in this new project's location instead of trying to go back to the original project's location. Check the publishing options, too.

That would be my first guess, anyway.