Hello,
i am not sure that i help you. But i think, you can save an origin file, after that can you delete all sheets excepting one and these one can you save and than you have to open your origin file once more. These procedure can you repeat until all sheets are saved. You can write this makro in a sidefile or you can run this makro after every opening of origin file (you can have a makro for open this file by closing of foregoing) where can you save, how many sheets were saved (when all, no macro will be started)...
Best regards
Jiri