List box
My form allows the user to select items from a list box and then preview the report. The first time I ran it the report ran for a single list box selection. Now when I run it (for whatever selection I make, irregardless) the form continually comes up blank, even after closing it and restarting the form. My first time with a listbox. Please advise.

Is it a multi select list box?

If not:
Have a look at your list box properties, Format, Column widths.
Have you got something like this?

0cm; 3.366cm

If you have it could mean your report is not getting the correct info. It may be getting the list ID and not what you are seeing displayed.