It does show that HP Photosmart C6180 is compatible with Windows 7 for both 64-bit and 32-bit computers.
The drivers come from HP to make their computer compatible with Windows 7. I would check the HP website to see if you have the latest driver set for your verison of the Photosmart printer.
http://h10025.www1.hp.com/ewfrf/wc/softwareCategory?product=1153494&lc=en&cc=us&dlc=en&lang=en&cc=us
If that doesn't help, you can post your question on the HP community website. http://h30434.www3.hp.com/t5/Printer-All-in-One-Install-and/bd-p/Install
Thanks,
Marilyn