You must be logged on to the computer as a user with administrative rights to install new programs and applications. Please see this article for a description of this situation. It's a bit complex, but you are being asked for your logon password to verify your identity as a user with rights (admin) to make changes to your system.
The alternative is to use the add printer wizard to install the printer.
If you're having problems with your printer, please be aware that HP has an excellent support site online at
www.HP.com.
I hope this information allows you to resolve this issue. If you need further assistance, please post back with a comment to this thread.
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