I used to be able to print in duplex. Recently, I happened to top up the paper into the paper tray while the printer is on, however, when pulling out the paper tray, there is a loud gear clicking sound. Thereafter, my printer just won't print in duplex.
I tried reinstalling my hp printer driver, however, my print still won't print in duplex. It shows that duplex is installed in the windows device driver setting, however it just won't print in duplex mode. I tried using my iphone to sent in a document wirelessly to my printer to print in duplex, but it just print my 2 page document in 2 separate pages instead of using 1 page on both sides.
I can see the duplex option in my computer as well as my iphone print app but it just will not print in duplex.
Could this be a hardware or a firmware corruption problem?