I've realized that the END statement doesn't always end my  program. I end
my program by placing the END statement in a particular form's UNLOAD event
so that the program ends even when the user clicks on close in the form's
control box. How can I solve this. I've noticed that this especially happens
when I double-click on the form's control box.

Try putting a loop before the end-statement like this:
        for a% = 0 to 9
                x% = doevents
        next a%

It worked for me. :-)
Best of luck,

Lea

A common cause is to hide a form which you don't need and then try to
unload the main form using Alt-F4. This stops the End statement of the
command button being processed and the hidden form stays in memmory
where it is still visible to TaskManager. Make sure all forms are
unloaded or add End to the unload procedure of the form which carries
the exit/control box.