I've noticed that after detaching and reattaching a screen session, I lose the scroll history. I have done some searching, but anytime I combine "screen" and "scroll" I get inundated with scroll wheel integration instructions.
Anyway, synopsis:
- In screen
- Large output
- Detach screen
- Reattach screen, but scrolling only produces blank lines at the top of the terminal.
For me it sounds like you scroll in your terminal (with you scrollwheel?). Of course your terminal emulator won't know the history of the screen.
To scroll inside screen you have to switch into copy mode (Ctrl A + [), then you can move around with your navigation keys (hjkl,left right up down;PgUp,PgDown eth).