QuickReport 1.0d - Printer selected is not valid ??

My application has several reports that are designed and printed using
QuickReport 1.0d. Every now and then when making changes in a report I
receive a message 'Printer selected is not valid', although other reports
will print correctly. Changing the printer for not-willing reports to - for
instance - fax output does create an output, but there's no way to get
output on my default (HP 820Cxi) printer.

Obviously, this is not a printer driver problem - or is it? Anybody seen
this problem and managed to solve it? The only solution I have foud so far
is to re-create the QR form from scratch.

Thanks!

M. van den Berg