>I use modeless report preview:
>
>REPORT FORM myform PREVIEW NOWAIT NODIALOG
>
>
>When user prints from preview by clicking printer button in toolbar, preview window remains open.
>How to force preview window to close automatically if report is printed from preview ?

One of the solutions is like this:

1. create a program, say closeafterprint.prg:
IF wexist("Printing...") AND WEXIST("Print Preview")
RELEASE WINDOWS "Print Preview"
endif
2. add a field to your report, and with expression
closeafterprint()

Good Luck