iMac USB ports not working

It's always helpful if you let us now what you've done to trouble shoot the problem before we post. However my first recommendation would be to do a SMC reset.

Regards,

Roger

Yes

http://support.apple.com/kb/HT1543

OK try doing a SMC and PRAM reset, follow these instructions to the letter:

1. Turn off your iMac and unplug everything from it for 30 seconds.

2. Plug in the power cord, keyboard and mouse only.

3. Press the power button and immediately hold down the Option, Command, P & R keys until you hear the second gong then release the keys. Your machine will start up normally, then check for the issues you are having.

Hi AB

Thats good advice from those above, but if in fact the USB port protection has tripped then you might get it to reset by disconnecting the power for 3 to 5 minutes instead of 15 to 30 seconds.

Also, try these steps: > http://support.apple.com/kb/HT1317

Dennis

I wasn't aware of that one, thanks Dennis.

Roger

Must be an older iMac as the new ones have 4 USB ports on the rear. I've had this problem before with non-Mac computers and was told that they are wired in series. So if one goes down, they all go down.

Sounds to me this is a job for someone who is a take down artist. From previous computers, these USB ports connect directly to an internal board that probably will have to be replaced. I think if I were you, I would be thinking about getting an estimate for the repair cost and if it's too much, a new iMac.

If your iMac supports BT, you might be able to get a BT keyboard.

It does sound like maybe a bad keyboard, mouse or a shorted cord on one of them, but you also might have a bad USB port on the back of the iMac...

Get a flashlight and your reading glasses and inspect all of the ports and cables for a bent or out of place prong.

Then after getting the ports to reset and the iMac restarted, try connecting only the mouse to one of the ports on the back first and then the keyboard to see which one is causing the issue.

If touching or plugging anything into the ports on the back causes a problem then there could be an internal short within the iMac.

I download - IOUSBFamily Log Release for Mac OS X 10.6.2 (Fall 2009 Systems)(IOUSBFamily-390.4.4-log on my iMac from the Developer Member web site and after instaling my USB ports are not working.

Can someboday please help me with this issue.

Thank you in advance!

Hi, I would see if I could beg or borrow a BT k/b & mouse...L

Wow. I have the same thing happening on an iMac 20" (Late 2008). Resetting the SMC changed nothing. I have tried all possible keyboard and mouse configurations, new keyboard and mouse, and even starting the machine with nothing plugged into the back of the machine, except the power (duh). The same "Over Current Notice" message pops up. This still happens when booting to an external drive.

Hi, I appreciate your concerns but hijacking another Post/Issue is best Not Done..

In any event if your Mac's are under Applecare - an Apple Approved Service Agent or your nearest Apple store is the best advice I can offer...
If you are completely out of warranty then an estimate from an Apple Approved Service Agent would be my advice..L