attachments

[Alyson]

When opening email attachments a box should pop up asking
if you would like to open the attachment or save the
attachment. Down the bottom there is a tick box which you
can tick so that attachments will automatically open and
it will no longer ask you. Well i have accidentally ticked
the box and want to get it back.I cannot for the life of
me work out how to do it? Does anyone have any idea?

Thanks
Aly