There are no drivers available for this operating system so you will need to use the Windows Update feature that it's built in the operating system. An active connection is required for successful connection.
Also, since the released drivers are available for Windows 2000, Windows XP and Windows Vista 32-bit, you will need to use the manual way of installing the drivers with Device Manager which can be accessed from Control Panel under the System category.
Download and extract the contents of the package (ignore the EXE file since it's an archive) to an easy to access location. Right click the entry in Device Manager and choose Update driver. At this point Windows will tell you that installing drivers that were not made for this version might cause trouble. Ignore this error and continue with the installation. When it's done, restart the computer and then you can use the printer. Make sure to select the Vista drivers as these are close to Windows 7 functionality.