I found these solutions on the web: http://consumer.installshield.com/kb.asp?id=Q108158
http://consumer.installshield.com/kb.asp?id=Q108322
http://www.installsite.org/pages/en/msifaq/a/1027.htm
http://www.annoyances.org/exec/forum/winxp/1008352528
http://support.softartisans.com/kbview.aspx?ID=904
http://forums.devshed.com/t32248/s.html
www.drtax.ca/download/public/isscript.msi Hope these lead to an answer.