Usb devices not detected

Please test it using other USB keyboard and USB mouse, and see the device status in the Control Panel (Control Panel, Device Manager). Is the keyboard item missing? Is there any USB item with an exclamation mark?

A USB hard drive is a portable external storage device that works just like a conventional hard drive. The device is simply plugged into a USB port on your computer as you would connect a flash drive. Unlike a flash drive, however, a USB hard drive can store a much larger amount of data. If your computer will not recognize your USB hard drive, you can try troubleshooting steps to resolve the problem.

Plug one end of the USB cable into the port on your hard drive and plug the other end into the USB port of your computer. Ensure that both ends of the cable are connected securely. Open "My Computer" (Windows XP) or "Computer" (Windows Vista/7). The USB device should be listed as "removable disk" once it is plugged into the computer. If it is not listed among the available drives on your computer, proceed to the next step. Ensure that the data cable is working properly. Sometimes they become faulty due to overstretching age or heavy objects sitting on top of them. Try another USB cable if you have one available. Disconnect all other USB devices from the computer as they may interfere with the operating system detecting the external hard drive. Reboot the computer if the USB hard drive is still not recognized. Plug the USB cable into another USB port and check to see if the device is detected. If you are using a USB hub, remove the device and plug the external hard drive directly into a USB port. If the computer still fails to recognize the device, the external hard drive itself may be experiencing a hardware problem. Check the status of the hard drive in the "Device Manager" window. Under Windows XP, right click "My Computer" and select "Device Manager." For Windows Vista and Windows 7, click the "Windows" button in the lower left corner of the screen, then type "Computer Management" in the search bar and press "Enter." Select "Device Manager" in the "Computer Management" window. In the Device Manager window, click the "+" sign that appears beside "Disk Drives." If the external drive is not listed, click "Other Devices" in the Device Manager window and see if an "Unknown Device" appears. Windows 7 First, please disconnect all USB devices and then perform the following steps:

Click "Start" button, type "devmgmt.msc" (without quotation marks) in the "Search" bar and press "Enter". Click "Continue" if necessary.

In Device Manager, double click to expand "Universal Serial Bus controllers", right click on the Host Controller, click "Uninstall" and click "OK".

Repeat the step 2 to uninstall all items under "Universal Serial Bus controllers".


Then, restart your computer and Windows 7 will reinstall all USB controllers automatically. If the hard drive that has failed is the same one that you are trying to recover from might the reason that you are getting this error. This could be an issue where the part of the hard drive you are trying to access is corrupt and not accessible which would explain the reason that it would let you access the other partition. Now I have seen cases where Malware can break the link of a Hard Drive. So let's try a couple of steps. Let's go back in to "Disk Management" Lets right click on the partition that you are not able to access and select "Change Drive Letter and Paths" Now try selecting a new Drive Letter. This will restore the path if it has been broken. The external hard drive may have been detected but the device is not working properly. If it is still under warranty, take the device to the computer store where it was purchased to have it repaired or replaced. Hope this helps.

hello,

For this you sholud go to in xp my computer ->right click ->manage->device manager->usb ->right click and give to all update driver this is valid also for win 7

Hello Prosper, I found drivers for a Sony Vaio VGC-LA1. It would appear that it is just a different name for the same model. These should work fine for you. Hope I have solved your problem, have a great day Prosper!

Based on what you have presented...
1 long 2 short - (Video Controller Failure or faulty add-on card

Do you have an installed video card? Does the unit have a built in Card? (In other words part of the mother board?)

If you have an installed card check that it is not loose... If it is still not functioning (and)

If your unit also has a built in video card that is disabled... go to the BIOS and enable it... see if your unit will boot up...

If the video card is not loose and you do not have a built in card... you may want to see if you know someone with an extra card to loan... or purchase a new one....

Watch this video tutorial ..

Part 1

Hi,

PCG-281L is the hardware configuration code of the computer. Based on the configuration code the computer belongs to VGC-LT1 series computer model. From the below link you can download the Manuals and Specs for this series models:

http://esupport.sony.com/US/perl/model-documents.pl?mdl=VGCLT10E&LOC=3

Thanks!!!!

Hi ,

Please try these steps that im mentioning and i hope it works out for you .

go to ?start ?right click my computer ?click on manage?device manager .You will see the drivers listed with a + sigh next to it .Look for universal serial bus controler and then click on the + sign nex to it ...then right click un uninstall usb root hubs so anything that has the word hub right click on it an then click on uninatall restart the computer and then check if the usb gets detected ...

If this does not work go to the hp website www.hp.com/support ,once the page opens up and where is says select a country or a region select united states then click on the arrow and where it says for product put the model no that is HP Pavilion a420n then click on the arrow and then select software and drivers downloads from the next page which will finally take you to the Select a download page then it shows you the compatible software and drivers.The fourth option saya BIOS IN BLUE cliclk on the BIOS update for A7V8X-LA motherboard and on the next page click on download .A dialogue box opens up so click on save and then save it on the desktop .Go to the desktop and then run it .Restart the computer and then it should work

all the best

Click Start
Click Control Panel
Click Classic View
Click System
Click Hardware
Click Device Manager

Does the 'USB' branch of the tree show the USB ports?
Is there an 'Unknown Devices' branch of the tree?

Either way, the software "device-drivers" for the USB ports are not installed, or not installed correctly, and so you'll get the symptoms that you've observed -- power without device-recognition.

Access http://support.dell.com and click "Detect My Computer", and download and install the device-drivers for the USB ports.

For anyone with a Big Disk drive that doesn't get recognised by Windows and gets a TUSB 6250 message in Device Manager, the cause is very likely to be the power supply. Although the drive will be powered up, it is not spinning at the correct speed. I tried all of LaCie's technical support suggestions, some of which are outlined above and none worked. They finally suggested getting a new power supply. This solved the problem (Wattac, £22). This problem has affected a lot of LaCie Big Disk owners...