Microsoft does not make the HP Deskjet 3600.... HP does. And HP does not make a Deskjet 3600, they make a Deskjet 36xx series which consists of the following 5 printer models:
» HP Deskjet 3620 Color Inkjet Printer
» HP Deskjet 3645 Color Inkjet Printer
» HP Deskjet 3647 Color Inkjet Printer
» HP Deskjet 3650 Color Inkjet Printer
» HP Deskjet 3653 Color Inkjet Printer
Click the link that matches your printer to see what drivers are available from HP.
If HP doesn't have a driver posted for your OS, then that leaves you with only one other source for the driver.... Microsoft. Click the Add New Printer Wizard
to see if this model is supported.