The proposed solutions under this forum as nothing but a piece of Cr()*&^)^&p. To say the least it is absolutly amazing to me that while the HP 2840 MFP printer will install and work under Win 7 and Win 8.1 perfectly well, the scanning functions WILL NOT WORK AT ALL.
This just goes to show the lack of qualified support from HP Corporate to provide a relatively simple driver function so that the HP 2840 MFP's scan functions will work.
In my opinion it is morally and ethically incorrect for HP to produce a printer product and to provide the appropriate driver support that is needed with today's computer OS.
Current economics force me to continue with this printer for the time being, but when it comes time to purchase another MFP printer I can guarantee it will not be a HP product of any kind.