Hi,

I want that Emacs starts with the frame/window configuration I saved 
before.
e.g. the whole screen is divided into two buffers side by side with 2 
different files open.

How to do that?

C-x r w r a (a as register a) I tried, but it does not save it.
C-x r w r 1 (Register 1 I tried) but it doesn’t save it

Because when I open emacs again, nothing is saved in my registers

I tried
C-x r j r a (a as the saved register) but it says, there is nothing saved

Where is my mistake?
-- 
Kind regards

Gottfried