This is frustrating!
I have a form which opens on startup, and this form opens a form conveniently named "frmHidden" in the background.
frmHidden runs some important "closure" tasks that need to be done when the user closes access.
The database has an extensive menu system that means that they can close the DB when any form is open, which is why I created this "hidden" form.
However. When the form is open, it still appears in the taskbar at the bottom, which I don't want.
If I highlight the form and click Window > Hide it does what I want.