I have an HP 4345 MFP that's printing nothing but blank pages when copying, sending a print job to the printer. Im not even able to print the config page. All comes out blank. Does anyone have any idea why this is? Thanks in advance.

If you are tec guy?
do half test page test find any image created on catridge drum, if no image found then
Check laser scanner assembly shutter fully operating or not while catride access unit closed, if unable to check, remove the shutter from laser scanner assm
Increase toner density
set factory settings,
If image on drum no print on paper, check transfer roller, contacts, if dirty replace T.roller, no result replace Power supply board..