Summary: After 2 hours of use, seems like the USB receiver died. Plugging it into different computers, USB device not recognized. I plugged in wired keyboards into the same port, they work fine. Tried the Logitech MK320 on other machines running win7 or win8, usb not recognized.
Summary: Now to see how Logitech's warranty service works.
Pros: The mouse still works.
Cons: I work at a Junior College, wireless keyboard and mouse are helpful when servicing students. We generally use the inexpensive MK270 which seems to hold up well. This was purchased for the reference desk. The keyboard went dead in less than 3 months service.
Excerpt: Staples only warrants this product for 14 days unless one purchases a Staples extended warranty. According to the packaging Logitech warrants it for 5 years, so one must phone Logitech, if and when there are problems. My keyboard wouldn't always interface w/my computer.
Excerpt: I purchased this wireless keyboard to use with my laptop placed on a riser to prevent "vulture neck" while using my computer. in less than 9 months, for not apparent reason, the keyboard just stopped working. Yes, I changed the batteries, rebooted the computer and "reset" it.