I had the same problem. When I finally reached HP about this they said that it could be my firewall. You can turn off the firewall then download.
I opted for the second solution, which worked just fine: uninstall, then reinstall the HP update program.
Click START, then CONTROL PANEL, then PROGRAMS AND FEATURES. Select HP Update program from the list, then click uninstall.
When this is finished, then reinstall from Recovery Manager. Go to this website: http://h10025.www1.hp.com/ewfrf/wc/document?lc=en&cc=us&docname=c00834921&dlc=en
It is called “HP and Compaq Desktop PCs - Performing a Software Application or Driver Recover in Windows Vista” if you wish to search it.
Follow the instructions at this site.
You can access Recovery Manager on the menu when you click START.