2 USB 2.0 devices not work on my mac only USB 3.0 Working
I've a MacBook Pro 15" Unibody (Mid 2012) . The USB ports stopped working a while back; i.e.: the computer would no longer recognize any of USB devices. They are all USB 2.0 devices (external drive, Flash drive, etc.).
I did some testing and confirmed that it does indeed not recognize any USB 2.0 devices. the computer works just fine with any USB 3.0 devices that I've tested it with.
I've already tried all the usual quick fixes: reset SMC, reset PRAM, etc.
What’s the problem is ? Is it a hardware or software issue?
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I am new to macs and recently bought an old iMac to learn. It's a late 2012 i7 with 16GB and a fusion drive. Runs a clean install of Catalina really well but it has a similar problem with USB ports. I figured it might be a hardware issue, but the similarities to the problem here make me wonder. Was this ever resolved for the OP?
In my case, I think I have reset SMC and PRAM following instructions on apple web site. USB3 devices seem to be recognised on all ports and I can read/write to them. I was able to create boot media for a fresh install, however the iMac will only boot from USB on the first port (closest to the thunderbolt ports). This is only a bootup issue. If plugged into any of the other ports, it can be seen and I can set it as the startup disk in settings, but it will not find the drive and timeout booting from internal disk. Booting to startup manager will only discover drives plugged into the first USB port. USB2 flash drives are only recognised in the first port at any time. Wierd!
par William Portals