This Topic should have been posted in Hardware Troubleshooting
Remove both Cartridges & Place them back again (read Instruction Manual). Now goto the "Printer ToolBox" in "HP Director" & Align the Cartridges thru the software.
this problm maybe occuring b'coz of Alignment Issue. thats why the Printer Prints the Test Page.
Have you updated the Printer Drivers. If not go here & select the OS & proceed.
Or go here for troubleshooting.
btw give detail of your PC config & OS u use.
If your Printer is 2 years old, then open it & Clean the Metal RAIL.