2.USB interface voltage is insufficient. When the mobile hard disk is connected to the front USB port, the system may not recognize the device. The reason is that the power of the mobile hard disk is relatively large and the required voltage is relatively strict, and the front-end interface may not provide enough voltage. Of course, inferior power supply may also cause this problem. The solution is not to connect the mobile hard disk to the front USB interface, replace the inferior low-power power supply or try to use the hard disk box with external power supply, if possible.
3. Compatibility between motherboard and system. Hehe, the most famous fault is the compatibility between NF2 motherboard and USB. If you encounter this problem on the motherboard of NF2, you can first install the latest USB2.0 driver and patch of nForce2, the latest motherboard patch and operating system patch, or try to refresh the BIOS of the motherboard, which can generally be solved.
4. System or BIOS problems. When you disable USB in BIOS or operating system, the system will not recognize the USB device. The solution is to turn on the options related to USB devices. That is, press F2 or DEL to start, enter the BIOS, and select Enable usb device.
5. Be careful when plugging and unplugging. Never unplug it when reading or writing, or it may burn the chip. There are more USB device icons in the taskbar of XP. When you open this icon, USB devices will be displayed in the list. Choose to disable this device, and then you can unplug it, which will be safer.
In fact, judging software and hardware problems is very simple. Just try it on another machine or another system. Some minor problems may be formatted with special software first. And remind everyone to choose FAT instead of FAT32 when formatting under WINDOWS.
Prompt unidentified USB device maintenance
The fault prompt is as follows:
Unrecognized USB device: unknown USB device. Many people have encountered a problem. For the operating system, the so-called "unrecognizable" is either a problem with the degree of driving, a problem with the USB device, or a failure in the connection between the computer and the USB device. The solution to the problem also starts from these points.
Different devices will have different treatment methods. It is helpful to know the conditions required for the normal operation of USB devices and some factors that may affect the normal operation of USB devices.
The following are some conditions to ensure that the USB device can work normally: (1) There is nothing wrong with the USB device itself-it can work normally when tested on other computers; (2) There is nothing wrong with the USB interface-you can test it on this interface by connecting other USB devices; (The driver of USB device has been installed correctly. If there is a detailed USB device, be sure to carefully check the corresponding documents and install the corresponding driver according to the instructions; Operating systems after Windows 2000 can recognize most USB devices, and operating systems before Windows 98 can install USB device drivers or universal USB device drivers.
The following are some situations that may affect the normal work of USB devices: (1) The USB device is out of order (the same situation was used normally before, but now there is a problem); (2) There is something wrong with the USB interface. For example, a. The polarity of the USB front interface is reversed, which may cause the USB device to burn. Be sure to read the motherboard manual carefully to prevent the wrong connection; B. insufficient interface voltage. This problem often occurs on some mobile hard disks. The USB interface behind the host is often more reliable than the USB interface in front. C. there is a problem with the compatibility between the motherboard and the operating system. Installing the latest motherboard driver can avoid such problems to the greatest extent; D. USB devices are prohibited in BIOS, which may be solved by changing the corresponding settings in BIOS; E. operating system problems can be solved by reinstalling the operating system; (3) There is something wrong with the USB driver: If there is something wrong with the driver, you should make sure that the latest driver of the corresponding model of the device is installed or make sure that the operating system does not need to install a special driver. The latest drivers can be found on the home page of online equipment manufacturers.
When there is a problem with the USB device, we should not only find a solution according to the actual error information, but also carefully check the specific brand, model and manufacturer of the USB device, and incorporate this information into the search results, so that it is easier to find the corresponding solution. For example, when some frequently connected USB devices are difficult to plug in and out, and the operating system keeps displaying annoying prompts such as "Unrecognized USB devices", you can temporarily close the corresponding USB ports in the universal serial bus controller or disable the corresponding USB devices in the device manager.
About unrecognized usb device computer settings
After insertion, some information that the computer is trying to connect to this USB device will pop up in the lower right corner, and sometimes a dialog box will pop up for the user to choose. Some users clicked No without seeing it clearly, or some functions of USB were banned because of some initial setup problems of the computer.
Solution: Right-click my computer and select Properties-Hardware-Drive Signature. Select Ignore here, and then click OK. Then plug in MP3. If you still can't connect, right-click My Computer-Properties-Hardware-Device Manager to find the USB controller, right-click and scan for hardware changes.
The voltage problem of the equipment itself
Because the current trend of MP3 is to do everything possible to reduce costs, the company constantly adopts new schemes, new controllers and new FLASH chips, which does not mean that these new things will cut corners. The problem is that these new things often need to be debugged for a long time to do their best, and the market situation can only allow MP3 factory testing to be put into production on one interface of a computer, so disconnection and disk dropping often occur.
In this case, users need to try several times, plug in different USB ports, and match a good quality USB cable separately (generally, the thicker the better, the copper is better than the iron), and then ensure the normal power supply of MP3 (try again with a charger).
The system reports "Unrecognized USB device"
Fault phenomenon: The computer accidentally loses power when using the USB flash drive, and the USB flash drive can't be used normally after restarting. After insertion, the system will report "Unrecognized USB device". Using other USB interface devices that can work normally will also prompt the same error message. Plug USB devices into other USB interfaces of the computer, and they can all work normally.
Fault analysis: Phenomenologically, the interface between USB device and motherboard is not damaged, and it is suspected that the accidental power failure caused the system setting error.
Solution: Enter the window of adding and deleting hardware from the Control Panel, delete all USB devices and reinstall the required USB device drivers. Restart the computer, and USB devices such as USB flash drive can work normally when plugged into the original fault interface. Unrecognized USB devices-notebook hard disk failure and mobile hard disk, plugged into the front USB interface, are unrecognizable.
This situation is largely due to power supply problems. Because USB hard disk also needs to consume a certain amount of electricity when it is working, if it is accessed directly through USB interface, it is likely that there will be insufficient power supply. Therefore, almost all mobile hard disks are equipped with independent external power supply or PS2 adapter, which is powered by keyboard. At this time, as long as the external power supply is connected in advance or the keyboard is connected through the PS2 adapter, try again after ensuring sufficient power supply for the mobile hard disk. You should be able to use it normally at this time. Need to remind everyone that it is recommended to ensure sufficient power supply before using the mobile hard disk, otherwise it is likely to damage the hard disk due to insufficient power supply.
For friends who have never used a USB external device, even if the driver is installed correctly, the system may not be able to detect the USB hard disk. This is mainly because the default CMOS port of the motherboard is closed. If it is not set to the open state, then Windows naturally cannot detect the mobile hard disk. To solve this problem, we can restart, enter the CMOS setting window, and set the item "Assign IRQ to USB" to "Enable" in the column of "PNP/PCI configuration", so that the system can assign available interrupt addresses to USB ports.
It is also possible that the USB interface type does not match, which makes the mobile hard disk unusable. For example, the USB interface configured by the computer is 1. 1 standard, and the purchased mobile hard disk is USB 2.0 standard interface, which requires that the cable connecting the computer and the mobile hard disk must support USB 2.0 standard. Because high-speed mobile devices are plugged into low-speed hubs, they may not be installed normally. Some friends use USB flash drives while using mobile hard disks. For convenience, they directly use the USB 1. 1 standard cable attached to the USB flash drive, which makes it impossible to correctly identify the USB 2.0 standard mobile hard disk. This fault can be solved by replacing the connecting cable with USB 2.0 standard.
Unrecognized usb device problems in the use of mobile hard disk
1, mobile hard disk box connects the hard disk. First, please set the jumper mode of the hard disk at the location of the main disk. Please refer to the legend of hard disk for jumper method. The connection method is to connect the external power supply first, and then connect the USB data cable after the hard disk rotates normally. If you don't recognize the USB2.0 interface, you can use the USB 1. 1 interface normally and install the USB2.0 driver that comes with the motherboard.
2. After the USB mobile hard disk is connected to the computer, the system does not pop up the prompt "USB device found".
There is no interrupt number assigned to USB interface in BIOS, which causes the system to be unable to identify and manage USB devices normally. Restart the computer, enter the BIOS setting window, and set the item "Assign IRQ to USB" to "Enable" in "PNP/PCI Configuration", so that the system can assign available interrupt addresses to USB ports.
3. It is suggested that the mobile hard disk should be connected to the USB interface of the computer's rear motherboard, and the mobile hard disk should be connected to the computer's front USB interface, usually with an extension cord, so that the on-board USB interface will be led to the front of the computer's shell, so that the hard disk will not work normally because of the increase in power consumption, and the system can't normally detect devices with correct names or only devices in mobile hard disk box, so it is naturally impossible to choose to install drivers and may not be recognized. The USB transmission line should be connected to the USB interface behind the computer, and the PS/2 auxiliary power cord should be connected to the keyboard or mouse interface of the computer for testing. Connecting PS/2 interface needs to be connected in the off state, and connecting USB interface after the computer is started.
Note: Because the BIOS version of the computer is different, please refer to the motherboard manual attached to the computer for specific settings.
4. If you encounter this problem on the motherboard of nForce, you can first install the latest nForce-specific USB2.0 drivers and patches, the latest motherboard patches and operating system patches, or try to refresh the BIOS of the motherboard, which can generally be solved.
5. When using FDISK format under WIN98/ME, it is impossible to correctly identify the capacity of the mobile hard disk, and it is also impossible to format the hard disk into FAT32 file system under WIN2000/XP.
Go to Disk Drive in Device Manager to find the removable hard disk, change its "Property Removable" option to unchecked, and then restart the computer. Our driver is not selected by default when it is installed, but if other USB devices are used, this option may have been changed to selected. Because 2000, XP operating system does not support FAT32 formatting larger than 30G, if you want to format it, you can go to 98 system to format it or use PQ and other software. 98 system does not support large-capacity hard disk partition, you should partition under WIN2000 or XP.
6. After accessing the mobile hard disk, the computer does not respond.
If the USB hard disk is connected according to normal operation, the mobile hard disk will not be displayed in the computer. You should check whether the item "Universal Serial Bus Controller" exists in "My Computer \ Control Panel \ System \ Device Manager". If it doesn't exist, you must restart the computer, press and hold the Del key when starting, enter CMOS settings, set USB control to "Enable" in "Chipset Function Settings" or "Integrated Peripheral", and then save.
Note: Because the BIOS version of the computer is different, please refer to the motherboard manual attached to the computer for specific settings.
7, mobile hard disk in win98/win me, the driver is installed correctly, but the drive letter phenomenon is not solved.
Please ensure that the USB mobile hard disk works properly in the device manager. If it is normal, enter the disk drive in the device manager, select the removable hard disk, click Properties, check the "Removable" option in the settings, and restart the computer.
8. Access the mobile hard disk before starting, and there will be double drive letters in the computer, with the same content or inaccessible.
Because some motherboard BIOS supports the detection of USB devices, after accessing the mobile hard disk, the motherboard BIOS will detect the accessed USB devices and automatically assign device numbers to them; However, when the operating system started, the system detected the USB device and loaded the USB plug-in device again to assign the device number, so the operating system appeared the phenomenon of double drive letters. Solution: Connect the computer to the device after startup.
Because computers generally can't turn off this function, USB products support hot plug function and can be connected to the product when the computer has an operating desktop.
9. Why can't I find the drive letter after connecting the mobile hard disk in 2003?
The partition of the mobile hard disk under the operating system must be specified manually. Ensure that the equipment is installed properly. (If the mobile hard disk device does not work normally, please refer to the installation method and precautions). You can right-click my computer and select Disk Management in the computer management window that appears. In the lower right corner of the window, there should be "Disk 0" and "Disk 1" (or more). The item "Disk 1" (which should be your actual mobile hard disk) shows the partition and each partition of your mobile hard disk in the following bar, but each partition has no drive letter. You only need to add a "drive letter" separately. Right-click the appropriate partition bar to display the drop-down menu, and select the option "Change drive letter and path" from the menu. After you specify the drive letter according to the screen prompts, you can finish.
10, there is a slight noise when shaking the mobile hard disk, and whether there are any components falling off.
This is because there is a certain distance between the balance bead and the disk surface, and it is normal to make a certain noise when shaking.
1 1, the speed of moving the hard disk. Usb2.0 moves the hard disk, but the transmission speed is similar to 1. 1.
If it is a 2.0 mobile hard disk, only the USB port of the computer is 2.0. If the USB port of the computer is 1. 1, then its transmission rate is also 1. 1. Generally, the transmission rate of 1. 1 is below 1M/S, and it is generally 2.0 when it exceeds1m/s. Different computer configurations have different transmission speeds. If the USB port of your computer motherboard is 2.0, please check whether the 2.0 driver in the universal serial bus controller of the device manager is installed correctly. In addition, in the USB port device settings of BIOS, the transmission modes are FullSpeed and HiSpeed. If everyone is USB2.0, let's set it to HiSpeed. FullSpeed is analog high-speed transmission, not as fast as HiSpeed!
12. Can it be used on a Mac after being formatted on a PC?
If the mobile hard disk is not common on PC and MAC, it can be formatted into MAC mode on PC with MACOPEN software (which can be downloaded from the Internet). If you have used MO, you will be more experienced in this field, because MO will encounter the same problem when formatting. But it is worth reminding everyone that even if the ordinary hard disk is formatted too many times, its life will be reduced.
13. if the mobile hard disk is used under operating systems such as WIN 95 and NT, the following solutions can be adopted:
Under operating systems such as WIN 95 and NT, because the system itself does not support any USB devices, and because Microsoft has not developed USB drivers under windows95/NT, it is impossible to use mobile hard disks. If this host is in the local area network, it can be accessed through other operating systems and enjoy this mobile hard disk.
14. In Win2000 or WinXP system, the mobile hard disk cannot be ejected and closed in the system.
Other programs in the system are accessing the data in the mobile hard disk, resulting in reading and writing the mobile hard disk. Close all programs running the mobile hard disk. When ejecting the mobile hard disk, turn off the virus firewall and other software in the system as much as possible.
15. Unable to boot the system from the removable hard disk.
Booting the system with mobile hard disk must be set to boot from USB device in BIOS boot settings. Set the "boot device" in the BIOS settings to "USB-ZIP". If the BIOS does not support it, you must update the BIOS version to the latest version.
16. There is nothing wrong with the product itself. Why can't it be used under win98?
There are two possible reasons. One is that the product is incorrectly formatted as NTFS format, so it cannot be displayed under WIN98. The solution is to delete the partition format under WIN2000 and above operating systems, and then reformat it. Of course, FAT32 partitions above 32G must be formatted below WIN98, and FAT partitions below 32G can be formatted under WIN98 or WIN2000/XP/SEVER. Another reason is that "movable" is not selected under "WIN98/ME". The operation method is as follows: In the device manager, add a new item under "Disk Drive" (before and after plugging and unplugging the mobile hard disk), select "Settings", select the "Removable" check box, and click "OK" to restart the computer.
17. There is nothing wrong with the product itself. Why can't it be used under WIN2000/XP/SEVER?
WIN2000/XP/SEVER are all operating systems based on NT architecture, with strict security policies. By default, they don't assign drive letters to mobile storage devices. This requires users to manually assign corresponding drive letters to mobile storage products. The operation method is as follows:
Right-click my computer->; Management->; Disk Manager, right-click the newly added disk-> Change the drive name and path. Click Add in the pop-up window. Select Specify a Drive Letter, and then click OK. At this point, open "My Computer" and you will see the newly selected drive letter.
18. Every time I install the driver under WIN98, I get an error. Why?
First of all, you can try to use Microsoft's own public USB driver (the driver is embedded in the operating system above WIN2000, so most USB interface devices above WIN2000 don't need to install drivers, and the driver can be found in Huajun Software Park with the file name of Microsoft USB storage Uddrivers.zip). If there is still a problem with the public version of the driver, please check whether the computer is poisoned and apply new antivirus software to see if it is effective; Another possibility is that there are some file errors in the operating system and the operating system needs to be reinstalled.
19. Why can't the mobile hard disk be used on the company's NT server?
Because WINDOWS NT does not support USB interface devices. This problem is not a product defect, but a Microsoft problem. Microsoft originally intended to add NT support for USB interface devices to NT SP6. However, due to the strategic adjustment, SP6 has not been released, but has directly introduced WIN2000, so USB interface cannot be used under nt.
20. The mobile hard disk has been used normally, but it can't be used normally after a period of time. Only the power light is on, the data light is off, and the hard disk itself is not faulty?
Frequent plugging and unplugging of USB interface may lead to logic errors of USB-to-IDE controller on PCB. At this time, you can open the product, remove the hard disk from the PCB, and connect the PCB and the computer with the original data cable. At this point, the data light goes out and the power light is always on, and the logic reset can be completed. Reinstalling the hard disk on the PCB can solve the original problem. Of course, many original mobile storage devices have little chance of this problem.
2 1, abnormal sound can often be heard when the mobile hard disk is connected to the computer, but it can still be used; I accidentally dropped my mobile hard disk, and now I can still connect to the computer. What's the danger?
Collision will damage the inside of the hard disk. Although it can be used temporarily, it is strongly recommended to back it up in time. After all, the loss of files will be great for everyone. If you have the conditions, you can find a manufacturer to do after-sales service. If it is a self-purchased product, the warranty is not easy or it has been over-guaranteed. It is recommended that users format the hard disk with "LFORMAT" and see if the original symptoms continue to appear every month, so they can use it normally. -This method is dangerous, so use it with caution!
22. When reading and writing data on the mobile hard disk, prompts such as "cache error" often appear. What should I do?
Generally, most of the above symptoms are caused by poor quality of the data cable or loose connection, so a new data cable can be replaced; You can change the Enable Write Cache option in the Disk Properties of the corresponding disk in Device Manager to see if the problem can be solved. If the problem of this equipment still exists, there are similar problems under multiple computers, and it is confirmed that there is no virus, which may be a hardware failure and should be repaired in time.
23. Users who use USB mobile hard disk sometimes encounter such a problem: some garbled directories are found in the hard disk, and when deleted with the delete command under Windows, the computer prompts that the file system error cannot be deleted! I want to format the hard disk, but there are many other important files on the USB hard disk. How to delete these garbled directories?
First, look for the cause of the problem. After many experiments, I found that the main reasons for the formation of the garbled directory are:
(1) Unplug the USB hard disk if it has not completely completed the reading and writing tasks.
(Read and write files when the power supply voltage of USB hard disk is insufficient. In the process of reading and writing one or more large files, the operating system will have a blue screen. This situation mainly occurs on notebook computers or when multiple USB devices are used on the same computer.
In both cases, it will lead to file system errors, which will lead to directory confusion. Knowing the cause of the problem will make it easy to solve it. This problem can be solved by using Windows Disk Scanner. Run the Scandisk command and choose to automatically repair errors when scanning the USB hard disk. After scanning, you will find that the garbled directory has disappeared, and there are some files with CHK extension under the root directory of USB hard disk. These are backup files of garbled directories, which can be deleted.
Therefore, when using USB hard disk, we should pay attention to the following matters: when reading and writing USB hard disk, although the operating system shows that the reading and writing task has been completed, if the reading and writing indicator of USB hard disk is still on, don't unplug the hard disk; When using USB hard disk on some computers or notebook computers with insufficient power supply of USB interface, it is best to use the external power supply line of USB hard disk to supply power to USB hard disk, so as to increase the voltage and improve the security of reading and writing data from USB hard disk.
24. Why is the USB2.0 mobile hard disk of Centrino notebook much slower under WINXP than under WIN2000?
The biggest possibility is that SP 1 or SP2 is not installed under WINXP operating system, so the corresponding USB2.0 driver cannot be loaded. Centrino is composed of intel855 chipset and wireless network card module, which supports USB2.0. However, the USB2.0 function of intel855 chipset must be patched under WINXP, and WINXP is activated for patching, so many users cannot experience USB2.0 on Centrino notebooks using pirated WINXP.