My late 2012 27" iMac has four USB ports on the back. Currently 2 do not work....most of the time. I had a mouse and a scanner/printer connected to them. I can use both using a USB port on my non-wireless keyboard and I can sometimes -- only sometimes -- use them through the ports on the back. This morning the rear ports worked OK but now after a shut down and restart when I was away during the day neither work. The other two ports work fine. The two ports that do not work are the two closest to the edge. The ones that do work (used for keyboard and Time Machine drive) are the ones closer to the center. What is going on? When I came back from vacation I had red ants crawling through the vents and across the screen (between the screen and the glass -- very strange). Could they have caused a problem? What can I do?
^if indeed there were red ants, then the best thing would be to have it opened at a service center...but i don't think they'd be the cause for your non-working usb ports... my very old white macbook had the same problem years back (with ants) and i had it opened in DH and found that they had founded a colony already inside...the tech had it cleaned, blow-dried, wiped and returned to top condition...but sadly it didn't last for a year when it broke down and died a natural death... as for the usb ports, they could have just "died" themselves and most probably because of a dead connection that would need replacement or soldering of that part in the board... other than that, a good Apple tech would do the job and not an ant exterminator cheers!
Thanks. I'll look for a good Apple tech. There are now a couple of Apple places here but the techs are in a different city.
Another symptom: the UBS port can charge my iPod Touch but the iPod does not show up in iTunes. The non-Apple, wired mouse works sometimes in the port but mostly it does not.
