I am experiencing this same exact problem - unable to get HP 2420 installed and printing, but it will print product info pages fine. I have been trying off and on for about a month and am about to throw this printer out the window. Please help.
If you want to use HP LaserJet 2420dn for Windows 7, You must install PCL5 Driver, PCL6 Driver and Postscript Driver in your PC. If HP LJ 2420dn driver was installed. Please uninstall it, you should install again by links below. Note: you must check your Windows 7 34 bit or 64 bit. Because the HP LaserJet 2420dn driver for Windows 7 32 bit and 64 bit is not same.
You can download HP LaserJet 2420dn driver by HP Support website:
Via alternative website which gives easy selecting OS to download it below:
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