With this icon you can delete all guidelines (though not grid lines) on the current page. Since this will also delete them on the associated master page, they will disappear too on all layout pages that use this master page. A safety query will appear beforehand so that you can cancel this function if it was selected accidentally.
When you click on this icon, the following dialog box appears:
With its help you can determine quite precisely which guidelines you want to delete, and where. As you may guess, selecting the upper checkbox deletes only horizontal guidelines, while selecting the one below it deletes only vertical guidelines. If you want to delete all guidelines on the page, you can of course activate both.
Selected line only checkbox excludes the other two. The
selection here does not refer to a guideline selected in the layout,
but to one selected in the guideline list described below.
In the popup near the bottom you can also select whether the deletion should apply to all master pages, or whether only the current master page should be affected.
As usual, [OK] confirms your selection, while [Cancel] quits the dialog without changing anything.