This HP Printer is compatible with the Microsoft Windows 8.1 operating system with a free full feature software and driver download from the HP web site at:
Can this printer be connected with a phone/answering machine? Will it work with the answering machine, voice messages going to the answering machine and faxes to the all in one printer?
Yes it can be used with an answering machine you just have to set it up initially to tell the printer if your sharing a phone line, have an answering machine and it will run a test.
This HP e-All-in-One does have the 50 Automatic Document Feeder (ADF) but does not have the Read I.R.I.S OCR software that supports the PDF file format.