I see all the posts that the HP driver for the HP Photosmart 7150 driver is not compatible with Windows 8.
That is not true. I had an old Dell PC which I upgraded to Windows 8 and then Windows 8.1. The HP Photosmart 7150 driver worked fine. Only after I bought a new machine with Windows 8.1 already installed did the driver not install.
I suspect the problem is that HP and the other printer companies have ccolluded to force us to buy newer printers. I had the same problem with trying to buy a new Surface. No printers would work with it. Then I discovered that Microsoft had two compatibility categories: compatible and basic compatible (basis wasn't the word they used). Anyway, what this means in corporate bull**bleep** speak is, you can't use the current driver to print highend pictures or something like that. But I just want to print ordinary stuff and I don't care what pictures look like. The newer format probably uses even more (espensive) ink.