Acrobat - "Document Failed to Print"

I put a new computer together (Core 2 2.4GHz, XP Pro, 2Gb RAM...) and installed Acrobat 4.0 for making pdf files with PDFWriter. Worked fine for several weeks but then I started getting this error message:


The pdf file is formed and saved okay despite the message. When I use pdf again, a new pdf is formed and saved okay and I don't get the error message. Here's the printer display:


I can successfully delete both print jobs using "cancel" When I do that and try to print a pdf again (with nothing in the print queue) then I again get the first error message. I tried uninstalling Adobe Acrobat 4.0 and then reinstalling it but no luck, same error again.

Having the error message apparently doesn't prevent the pdf file being formed and saved, it's just an annoyance, it only started doing this last week. It's an interesting problem but I haven't found the solution yet, any ideas?

Bob