Hello,

For some time I'm having problems using USB and different devices on my Windows XP Desktop, I have a motherboard with 6 usb slots, but because it's hard to get to them I'm using a cable and one USB slot.. At the beginning I remember I had no problems, I could use different USB keys, my mobile phone and my mp3 player..

However, after a while it started to not find my devices, when I put my mobile phone, it doesn't show the memory card as removable disk L: I need to remove it and put it again and usually after ~5 or 12 put in and put out into the usb it shows up.. the same is with my mp3 player, but now it got mad at all, whenever I put an usb key to do something, it shows a drive L: and the icon is like a folder, but when I try to access it it says that it is an unknown device, no matter how much times I put my usb key it's always the same..

Anyone had these kind of problems and are willing to help me out? I'm really fed up connecting the devices over and over again until I succeed and I don't want to reinstall, so maybe there is a way to reinstall only devices or something like that? that it would be fresh and later I could use everything normally? any suggestions?

Try uninstalling the drivers and then removing the ports from the device manager. On the next reboot, Windows will re-detect those devices and re-install the drivers. Also, make sure you haven't changed the USB settings from the BIOS. I have had problems with USB devices when switching between Hi & Full Speed.

Actually it's not the driver issue. It's more of a physical contact issue that is causing the problem. A normal USB socket and plug has a lifespan of about 600 to 1000 mating cycle. After which, it's up to you luck whether it continue to work or not. USB sense it's device via the resistance that present at the end of the device. Different value will indicate different speed capability. So, when the contact is not well done, the resistance can't be sense properly, or it fall out of expected values, that when you get the "unknown device" popup.

Since you're using a cable to extent your usb port from the back, which is a wise choice, as replacing an extension is easier and cheaper than replacing those on your motherboard, in which case you might have to change the whole thing. So, what you should do now is to try your devices on those different port at the back of your pc. See if the other 5 works. If it does, you need to change your extension cable. When you get a new one, try look for those with thicker wire, as it can carry more current, which will give you less headache.

If all the other port behind is not working well also, then you might need to test your device on another machine. Since the same lifespan applies to the plug on your device as the socket on your motherboard. If it fail indefinitely, then it's time to change your mobile phone usb cable or your mp3 usb cable. As for your thumbdrive (usb key), you can try a trick, which I did to mine, by pressing the metal casing of the plug itself. Make sure you know what you're doing, and I won't be responsible for any damages that might happen to your thumbdrive. If possible, try to backup first. So, after pressing the metal casing, you should be getting a tighter fit when you plug in your thumbdrive. That should extend it's lifespan for another 100 mating maybe.

This is one problem commonly people don't notice. With lifespan of 1000 mating cycle, if you plug and unplug your usb 5 times a day, could be more if you're a busy person and not working within a networked environment. That will leave you 200 days of usage. Working 5 days a week, so you can expect your thumbdrive to last about a year or so. By then, you could be tempted with buying a new one with bigger capacity and at the same price or even cheaper than the one you bought. The 5 years warranty will never be useful, unless you're the unlucky person to get one with defect that dies within a year. Worn out plug can't entitle you to warranty claim as it doesn't cover normal daily wear and tear.

I reinstalled my mobile device, mp3 and usb keys through the device manager and it seems to work now..

faulty.lee before that I tried to change the usb cable from one usb port to another and it didn't change nothing, it gave the thing that "found new hardware" and again it tried to install it, now when I reinstalled, I just hope it will continue to work normally..

I think it could be a hardware issue as well. From your initial description, I sounds like you tend to swap out many devices as you need them via one usb extension cable which is plugin the back. Maybe there is residue build up on the metal connectors of some or all of your usb devices. I recommend you clean them with a swab and some alcohol like solution which will remove the oxidation. Lint, dust, oil from hands, and other air borne particles also contribute to this.

If it is not oxidation then the culprit could be your extension cable. Maybe it is not usb 2.0 or performance/power rated. Could it be kinked in any way, stepped on, or rolled over by the wheels of a chair? Sometimes static charge also builds up within the cable or it receive interference from the other cables it is run by.

If these are looked into and don't help maybe it is the usb ports component on the motherboard that is giving out or the solder is cracked.

This concludes all of the most likely hardware problems that you might encounter.

• Have you changed the polling frequency for your USB ports (i.e. for "speeding up" the data transfer rate of your mouse)?
• Kind of basic: Have you overclocked your PC?
• Another basic: Have you changed anything inside your PC lately (around the time the problems started occurring)?

This post has been edited by xerxes: Sep 14 2008, 11:52 PM

if u can see USB at boot time them it means ur port is good and usb is fine the drivers in ur OS is *****edup
try uninstalling driver from hardware management then reinstall via hardware wizard

If you are having USB problems, it is highly there is a hardware related problem either with the motherboard itself or connections between the USB port and the motherboard connector.

You may also want to check whether there are problems with the USB drives itself, or its connection with the USB port.