[PeterReaper]

@ Comment #4

Your suggestion worked! All I had to do (after your procedure) was to reinstall the Logitech Setpoint driver to get my MX518 mouse to be recognized again.

Thank you very much!!!

[Cadian_207th]

Thanks dudes, especially to the dude that mentioned pulling the plug. I owe you a pizza!

"The Emperor protects. But he doesn't do tech support when the Machine Spirit fails."
-BF

[Dr_Acula]

Well if you ever decide to visit this little town called Adelaide in Australia I'd be absolutely delighted to share a pizza with you. And I'll pay. Bother these so called experts in microcontroller design who forget basic things like how CPUs fail. The space shuttle has 3 seperate computers, two of which have to agree on an output before a decision is made. Computers are unreliable and those experts should know that. What I would dearly love is someone who designed the USB system to post on this forum. I'd like to discuss failure modes and watch dog timers with a designer. Pulling out the power cord should not be the solution!

[Wigl4me]

If your problem comes from an ASUS Motherboard, I just had the same issue and resolved it through much trial and error. Of course, MOBO's vary but through research, I have found many others with ASUS MOBO's (All different types and models) have had the same problem. Here's what I found... Most motherboards (Asus or not) have multiple connections for usb outputs. Your MOBO is designed so that if one USB output fails be it from a shorted device or component failure, it will only effect the output connected to that device. (However, if the failed output is left connected, it could effect the others until you unplug it) So..if you plug a device into one usb port and it's not recognized but is recognized in another, most likely, that usb output is bad. The failure is usually a voltage issue. You can test this with a meter. Your output voltage should be around 5 volts. Anything less than 4.75 volts will allow your computer to see the device but not "Recognize" it. (Be aware, going into your bios and looking at your voltages will NOT show you a failed usb port as it takes an average of ALL voltages for ALL usb ports.) To rectify this, you must open the computer case and move the connection cable from it's present location to a spare one on your MOBO. If you have none which are spare, you could replace it with one you don't use or don't use as much. i.e. if you use the front usb's and not the back, you could switch them. ) Anyway, I had this issue. As it turns out, my computer has "Memory card reader slots" which had shorted out at some point.(They are usb based) I removed the connection and moved it to another location and the problem was solved.

Mod edit: remove email address

[zutuztu]

boy oh boy a had exactly the same problem and pulling the plug did it!
thanks again!!!!

[mattglop]

Hey everyone, I am having a similar problem.

o, two days ago I was rendering a video on an editing program, and a notice came up saying I was out of memory. My external HD was in the computer at the time, because I put clips from there into the videos that I render.

Since then, USB devices that previously worked are working anymore (external HD; printer), besides my mouse. Whenever I plug one into the USB port, it comes up with a yellow triangle with an exclamation mark on the bottom right of my screen saying, "One of the USB devices attached to this computer has malfunctioned, and Windows does not recognize it."

I have a Dell Inspiron E1705 laptop.

I have heard of people with this exact problem. Many of them simply unplug their computer and it is fixed. I have tried doing that, but I feel it may be different, since I have a laptop.

I have tried reinstalling drivers, and uninstalling the hubs in device manager as well. When I contacted Dell, they came to the conclusion that I need to reinstall the operating system...

Do you think I should take the battery out, and leave it out for a longer time...? The longest I have left it out is 7 hours.


Thanks,
Matt

Edit: So, it has been found that when the USB 2.0 Driver is disabled, the laptop will recognize the USB devices that it hadn't before. Only problem is it will be much slower. Anyone know how I could fix my USB 2.0? I have updated the driver.

[amy_schlemer]

Originally Posted by Dr_Acula

I've just been through all this as my computer suddenly decided to stop recognising all the USB devices. Have done ALL the things above including twice deleting all references to USB hardware in system manager and the registry and rebooting whereupon windows then reinstalled all the USB hardware. It STILL wouldn't work.

Then I remembered the schematic of a modern PC power supply. Turning the PC off doesn't really turn it off as the motherboard is still powered. So I pulled out the power cord, waited 30 seconds and put it back in. Et Voila! USBs all working again.

My theory is that the USB driver has an internal microprocessor and it needed a reboot. I wonder how many PCs get taken to the repair shop with this problem, are unknowingly 'fixed' when the power cord is unplugged, and the repair guy gets all the credit for fixing the problem without having to do anything!

I tried this and my USB ports still do not work. My jump drive will start blinking with a very dim light and then it will pop up saying that the device is not recognized. My mp3 player will charge but will not be recognized either. Why is that?

[Benbiz]

I had the same problem, started 3 days ago. Computer was workiing fine, but noticed when i put my Iphone on the cradle, I got that Not Recognized pop up. It was driving me crazy. This site was my last hope before I took it to a shop. I tried the unplug thing and hot-damn it worked. Thanks Dracula. I have been going crazy. You deserve a Nobel Peace Prize, in the catagory of logical thinking. Take care.

[scottw57]

I've been working on this USB issue all day...did everything...finally found your posting and solution..I only had a few devices that were not working..wasn't the actual port..my mouse and keyboard worked but not my smart phone or external hard drive . I shut down the computer many times to no avail..then I did what you said and just unplugged it and to my astonishment it worked. You just made my very bad day great. Thank you so much!!!!!!