Thanks, Cetin. In fact, I searched MS's site and lucky I found a work around. It seems due to something on the numeric coprocessor by HP's driver. I just need to install the Visual Studio Service Pack 3 to solve this problem.
http://support.microsoft.com/default.aspx?scid=KB;en-us;q183522

>>When I set the default printer to HP 840C or 1125C and after use the 'report' to preview or print out, release the form, the whole windows (98 or ME) will be hanged.
>>report form (cRptName) noconsole to printer prompt
>>or
>>report form (cRptName) preview
>>I have tried to use HP 810C or Epson printer driver, don't have this problem.
>>Any suggestion how to solve this problem? I am using VFP 6.0 English version running on Chinese Windows.
>
>Power,
>HP printers are famous to have driver errors. Check KB article Q183522
>Try to use a driver that ships with win (choose one closest). Also HP site might have an updated correct driver.
>Cetin