Change and Save Sheet Default Size

After updating my software, all of my "B" sized drawings have reverted to the default "A" sized drawing, When I change the drawing size by using  "Print Manager"  and then save it, the print size problem reoccurs when I reopen the drawing. How can I change the "default size" and/or how can I save it in the correct size without have to resize the drawing each time I open It and then print it?