USB 2.0 storage device malfunctioned in Windows XP. Unknown Device!?!

Umm, i dont if this will work, but on my old pc, i used to get this all the time when i plugged usb devices in, turned out, my power supply was not powerfull enough and there wasnt enough power to supply the USB port, so they we malfuctioning.

I''d recommend taking out all uncessary devices, and if still no joy, upgrade your power supply.

This is only something that could work, i dont know if its the same thing as i had.

Regards,
Dan

The fix/cure I gave relates specifically to machines that have always had a sufficient power supply. In my case, the error occured 'out of the blue' on a PC that had always maintained good power and nothing new had been added that might have exceeded its capacity.

I would agree though that USB powered devices being added over time will put extra strain on a machines PSU and that users should be aware of this being a possibility.

unknown device problem - fixed !!!

I was having the problem of my 2 week old, 2Gb USB 2.0 Flash drive suddenly becoming an 'unknown device' when I inserted it into any one of my USB ports.

All my other usb devices were working fine (printer, scanner, 2nd usb drive and mp3 players). The device mentioned previoulsy just refused to work.

When I tried the fix suggested by Technophobe, my usb flash drive was detected instantly and recognised as it should have been.

Tecnophobe, you're a champion :angel: Thanks heaps !!!

Matt (bluegreen) :grinthumb

I hate to say Me Too!! but I am also having the same problem with a laptop drive in a usb adapter case.

I worked for about a month on one pc but then I started getting the blasted unknown device messages, so then I started using a different pc and shared out the drive and that lasted for about a month.
well sad to say I am running out of PC's the plug in and share the drive.

I also tried the external power supply and that didn't help.

I also tried the driver disk and a uninstall and reinstall cycle and that fixed one pc but of course not the one I like to.

Just another good reason why linux is such a better OS then win.

ttfn

Read the FAQs:

http://www.techspot.com/vb/topic45947.html

Technophobe, the fix you mentioned got me thinking. One trick you can use when you cant get your pc to boot is to disconnect the pc from the main power at the wall, just as you described, but hold the power on\off button in for about a minute. Then hook up and boot up. This often works and it seems to be related to what you are describing. Now the reason it works for what i am describing is that there is circuitry inside power supplies that gets "messed up" for lack of proper terminology, and the holding in the power on\off resets the internal circuitry of the power supply. I am thinking these are somehow related. It could be that some circuitry in not only the power supply could be at work here but also some circuitry on the motherboard as well. Its hard to say, only a guess, but there seems to possibly be some similarities here. Either way, if it works, it works, lol.
Thanks for the tip!

You're all very welcome!

As you say, if it works, it works

Yep it worked

i had the same problems as everyone else in this thread so i did what technophobe suggested, i turned off my computer disconnected the power waited thirty minutes and what do you know it all works again Thanks Technophobe ur a genius.

Thank You Thank You Thank You

When it comes to dealing with windows xp errors it's never simple to resolve

Rename this, delete oem blah blah blah inf that, patch this, fresh install that

After so many years of being taught that I forgot that sometimes it the simple things that are the most profound

This is the case with the USB mass storage device driver going south

I searched for weeks and everyone had their own "solutions" none of which worked

If it was suggested to wave a dead chicken over the box I would have done it (i was freaking out)

What...? All I have to do is turn the computer off, unplug it, wait 30 minutes, replug and boot up

I'm one of those types who leaves their computer on all the time so to just turn it off was not even on the radar screen

Well I'm here to tell you THAT IS the fix

After I did that everything came up like it should

Again, thanks

I'm just glad I was able to help someone... anyone... really, just one person finding a fix is good.

And how did you know Bob was my uncle?

Thank You Technophobe!!!!!! It Worked!

THANK YOU!!!!THANK YOU!!!!THANK YOU!!!!THANK YOU!!!!THANK YOU!!!!THANK YOU!!!!THANK YOU!!!!THANK YOU!!!!THANK YOU!!!!THANK YOU!!!!THANK YOU!!!!

OMG! I can't believe that worked!!! You saved me hours of frustration!!!!!!

THANK YOU!!!!THANK YOU!!!!THANK YOU!!!!THANK YOU!!!!THANK YOU!!!!THANK YOU!!!!THANK YOU!!!!THANK YOU!!!!THANK YOU!!!!THANK YOU!!!!THANK YOU!!!!

You're welcome

"unknown device"

I had similar problem -while connecting usb devices I got errors,

and I solved it by updating the bios version.
I used MSI motherboard, and it solved few other problems as well.

Great Advice

I just wanted to say that this works i got my external hardrive back and my printer, thank you for posting this tip.

usb 2. fix works

Just a word of thanks to technophobe. I had the identical problem and got advice from Sony to take everything off in safe mode and if that did not work to do a system recovery (just what I wanted to hear) and if that did not work to get the computer repaired.

Incidentally, pulling the plug from the wall has been a useful technique with cordless phones, my multifunction HP printer, modems and other electrical items. It is important to remove the plug from the wall. Just removing the electrical cord from the back of the computer does not remove the charge that is probably located in the transformer (capacitator).

Hi.

I just registered to thank technophobe for solving my usb problem.
Thank god google pointed me to your post (although it was on the second page of the search).

They should put the solution on the first page of the computer manual.

I would have NEVER come up with the solution on my own, and would probably have thrown the computer out the window.

Thanks again!

Thanks Everyone

My usb nightmare began when I had my EOS camera hooked to the computer and took a shot. Most everything became an "unknown Device". I gave into tech support at Canon to no avail.Tried just about every fix I came across. Finally after so many hours of life never to be lived again All I had to do was unplug my computer for a couple of hours. This completely fixed all my USB problems. Thank you everyone for your posts.

thanks

I just wanto to say hello to all and a big thanks for your tip. It saved my work day

sorry, but I have another problem
I have my optical mouse using USB port and it worked well, but suddenly it stop working, I check with 4 USB ports and none works
I think my USB ports were all dead, but when I pluged my USB drive, it still worked well..
and sometimes I tried to pluged the mouse again, and it worked for a while, but after that it stopped..

so the problem is my mouse or my system ??

thanks for all your help..

My problem is very similar, but I haven't been so lucky to get it fixed. Same thing happened to all USB devices connected to my PC yesterday, they all stopped working and I'm getting bunch of error messages in XP sending me to troubleshooting(which is worth nothing). Anyway, after few hours, fresh reinstall I found out that unplugging power cord does help. But, it only helps for few seconds(at least in my case), sometimes minutes... For example, my laser mouse which lights up every time the PC boots up, stays on for only few seconds and then becomes unusable just as before. I left my PC unplugged all night and this morning I was able to get USB working literally for 20 seconds. I know for sure that my mouse is working properly cause I tested it on other PC. The things is that there is something else, besides residual power on MB that creates all this bs. The residual power is one thing and that other thing-I haven't figure out that one yet?! Any other ideas on next step?

I have to say that while I was troubleshooting for that I noticed that my case was very static. I checked grounding, outlets and everything seems to be fine. hmmmm