Sometimes when I open a workbook it 'isn't there' in normal view. The
toolbars are visible, but the sceen is otherwise blank with no scroll bars.
If I switch to Print Preview, the document appears - but cannot be edited of
course, and if I switch to Full Screen it also appears - but there are no
toolbars so editing is limited. every time I return to Normal screen it
disappears again.

I have seen the suggestion on these forums that it could simply be 'off the
radar' - i.e. moved out of sight on the screen - but without scroll bars
there is no way of retrieving it.

Sometimes the same workbook opens normally one day, but not the next. I am
running 2003 but have a 2007 trial installed and the problem was there before
I installed the 2007 trial.

Any suggestions please?