Troubleshoot problems with mobile hard disks that can't be displayed on my Computer

The newly bought mobile hard disk cannot be displayed on my computer, but the lower right corner icon shows that it is connected, what is the problem? XP and Vista systems have all been tried, and I don't see a removable hard drive on my computer.

A: Is the new one not yet zoned? Of course it doesn't show.

After inserting the mobile hard disk, my computer-right key-management-disk management, which should be able to see your mobile hard drive, should show the unpartitioned, you partition and format the good.

A: Possible reasons are as follows:

1, your mobile hard drive does not have the partition.

Right-click on My Computer--manage--disk management--Does the right window see the removable hard drive letter? If you can see it, right-click the format.

2, if already partitioned, try the following method

To the system directory c:windowssystem32drivers see if there is a Sptd.sys file. Remove it and reboot.

Try the following two ways to resolve:

First, the auxiliary software repair method. Choose "Super Magic Rabbit", the advantage is very simple operation: start software → "advanced hidden" → "Disk and folder", will u disk letter "√" removed, click "Save" after the withdrawal of the computer, the problem can be solved;

Second, modify the registration form. "Start" → "Run", enter regedit

Open the Hkey-current-usersoftwaremicrosoftwindowscurrentversicnpoliciesexplorer branch in turn, remove the NoDrives key value, and turn off the registry to restart the computer.

If not, change the socket to try, not yet, on the reload USB drive try.

3, if the above methods can not be solved, the explanation is that the power supply is insufficient.

You can try the USB jack on the back of the computer.

If your computer has hardware such as an optical drive, floppy drive, or a burner, you can disconnect the power from them, which reduces power. See if it can be displayed. If you can, just change the power.

A: USB is not recognized by the computer, if the system or system with the driving reasons, generally after the restart can be restored or power-on press F8 into Safe mode in the exit, in the normal mode (repair damaged registry).

U disk inserted into the computer, the computer prompts "unrecognized device" Troubleshooting methods are as follows.

1th step: if u disk insert computer, computer prompts "unrecognized equipment", the U disk power supply circuit is normal. Then check the USB connection circuit failure of u disk.

2nd step: if u disk USB interface circuit is normal, it may be a clock circuit failure (U disk clock frequency and computer can not be synchronized). Then detect the crystal oscillator in the clock circuit and harmonic vibration capacitance.

3rd step: If the clock circuit is normal, it is the main control chip poor work. Detection of the main control chip power supply, if the power supply is normal, then the main chip damage, replacement can be.

There is also a reason is that the USB interface is not enough power, may be the USB interface attached to too many peripherals caused by insufficient power. It is recommended that you use a live Usbhub or a PS/2 adapter using a USB switch. It is also possible that Windows XP by default to open the power-saving mode, resulting in insufficient USB interface, so that the USB interface intermittent failure. Right-click My Computer/Properties/hardware/Device Manager, double-click the Universal Serial Bus controller to several USB

Root Hub "Double-click any, open the Properties dialog box, switch to the Power Management tab, remove the" allow the computer to turn off this device to save power "before the check, click OK to return, in turn, each USB

Restart the computer after the Roothub properties have been modified. USB device can restore stable operation, the frequency as low as possible.

If you need to install drivers, it is recommended that you install Drive Wizard 2008

, after installation, use its automatic Update drive function, it will automatically download and install the latest version of the driver, including network card, sound card, video card, USB, etc., eliminates the search and installation of the pain.

Drive Wizard

Http://www.onlinedown.net/soft/3450.htm

If there is a letter but not shown, workaround: Right-click My Computer/management/storage/Disk Management, then right-click the removable disk icon click the Change Drive and Path option on the shortcut menu, and then click Add in the subsequent interface, and then select Assign drive letter. Also, select the appropriate letter from the Drop-down list next to the option, and click OK. When I finally open my computer, I can see the drive letter of the flash memory.

USB storage Device not recognized

When you want to use Flash or mobile hard disk to exchange data with the computer, but plug in the USB port when you find that the system can not recognize the USB device, what is the cause of this, I would like to briefly troubleshoot the USB storage device itself after the failure of the cause of this phenomenon.

1. Front USB cable Connection is wrong. This type of failure occurs when the USB cable on the motherboard corresponds to the front USB connector on the chassis, which is also quite dangerous, because the positive and negative connection is likely to cause the USB device to burn.

2.USB interface voltage is insufficient. When the mobile hard disk is connected to the front USB port, it is possible that the system does not recognize the fault of the device. The reason is that the power of mobile hard disk is relatively strict, the front interface may not provide enough voltage, of course, inferior power supply may also cause this problem. The solution is to move the hard disk do not connect to the front USB interface, replace the inferior low-power power supply or try to use the external power of the hard disk box, if there are conditions.

3. Compatibility issues with the motherboard and system. Hehe This kind of fault is most famous is NF2 motherboard and USB compatibility problem. If you encounter this problem on the NF2 motherboard, you can install the latest NFORCE2 dedicated USB2.0 drivers and patches, the latest motherboard patches and operating system patches, or not, try refreshing the motherboard BIOS can generally be resolved.

4. System or BIOS problem. USB devices cannot be identified in the system when you disable USB in the BIOS or operating system. The workaround is to turn on the options associated with the USB device.

Failure performance of USB interface with insufficient power supply:

1, the system can not find the mobile hard drive, the status of the mobile hard drive light is not bright (green flash for the read disk) or keep your for green (red for the read disk). It may also be accompanied by a rhythmic "click" of the hard drive, as if the hard drive were faulty.

2, the system can find new hardware, performance for the new hardware driver also installed normal, but in my computer without the letter display, can not use the mobile hard drive.

3, the system can hit the mobile hard drive, also has the letter display, copy small file normal, but copy large files easily lost data, resulting in the copy to the mobile hard disk file can not open.

4, more serious is the host after the mobile hard disk, the host can not start, prompted the system files are missing or boot disk without system files and so on.

The solution to the problem of insufficient power supply for mobile hard disk:

1, for the motherboard on the USB interface has jumper can change the power supply mode of the host

When the mobile hard disk can not be used normally, we can try to change the power supply channels, the original deputy power +5VSB power supply to the main power +5v power supply, see whether the mobile hard disk can be used normally.

Note: We usually use the ATX V2.1 version of the switching power supply, can only provide +5vsb1.5a current. However, in fact, most switching power supply manufacturers in the production of switching power supply in order to reduce production costs, for the +5VSB power supply of the use of low-frequency Transformer direct step-down, and then through the 7805 voltage regulator block to provide to the host; some use a single autofrettaged excitation switching power supply circuit, there is a separate 3-5w transformer 12V DC voltage, again after 7805 voltage regulator provided to the host. Auxiliary power in the main role of the host is to provide the power-on circuit, network wake-up, M wake, keyboard boot, and other functions, in general, this part of the circuit for the auxiliary power supply of the current is relatively small, so most hosts use this type of power will not produce any problems. Since 7805 can output 1.5A of current in the case of a standard heatsink, manufacturers in the production of most do not use the heatsink or the use of small fins, so the output of its radio is only 500MA, especially in the long period of large current work, because 7805 calorific value, output current will increase with the temperature of the work down, to the cut-off temperature The output is stopped when the degree is. So when our motherboard USB interface is using +5VSB power supply, then we use the mobile hard drive, there will be problems.

For a host that can only be powered by a secondary power supply, if this problem arises, try replacing the switch power supply with the high-power brand name to solve the problem.

2, for the power supply current is strictly limited host

Because motherboard manufacturers to ensure the normal performance of the motherboard, using electronic circuits to ensure that the current output of each USB interface is 500MA, so for mobile hard disk can not be used, we can only replace the large capacity of Low-power 2.5 "hard disk use, or the use of external power supply of mobile devices to ensure its normal use."

3, through other USB interface or PS/2 interface auxiliary power supply

Two USB connectors under the keyboard and mouse, its power supply is and keyboard mouse taken from the same road, its PCB board circuit most of the board is directly linked together, so when the mobile hard disk can not be used, even if we plug in the PS/2 interface, the increase in the current will not have much change, Mobile hard disks are still unavailable for most of the time. At the same time, it is also possible to burn the interface and control chip when the PS/2 interface is plugged in, requiring special attention. Generally, the USB interface of the mobile hard disk power supply are directly from the USB interface +5v. Note that some mobile hard drives will have two and together USB interface, but the side of that is not the data interface, but when the main USB data interface power supply is insufficient, in order to assist the provision of large current to ensure the normal operation of the mobile hard drive set. But in fact the power of the two or two USB ports on the motherboard that is behind it is taken from the same path, in other words, regardless of the use of one or two USB devices, the total power supply is limited to a certain range, especially for the host of poor performance or power of small power supply performance more obvious. So when we encounter more than 40G of high-speed mobile hard drive, there is often a lack of power, can not use the normal situation. At this point, even if we put two USB connectors are not able to meet the hard drive power requirements, still not available. However, this is the case for the 4 or 6 predecessors, or a rear USB interface of more than 4 can be used, because the USB interface is usually powered by a USB HOST hub support two USB interface, a group of power supply, a different set of USB interface to use a different power supply. Note that you must not connect to a set of USB connectors.

4, the use of external power supply direct

For a 3.5 "removable hard drive, because of its high operating current, so the mobile hard disk box supporting this kind of hard disk use external power supply to provide additional +12v and +5v power supply, so basically does not exist because of insufficient current power generation" can find the mobile hard drive but in ' My computer ' without the letter display " of the situation.

For 2.5 "40G above the mobile hard disk, because of its increasing working current, individual high-speed hard disk +5v power supply has reached 1 A, so rely on the USB interface to provide the hard work of the working current can not meet the normal work of the hard drive. Most of the performance is: the mobile hard disk in the part of the machine to work properly, only removable hard drives can be found on some machines, but there are no disk characters to display, some can sometimes read the disk on some machines, sometimes they can't read the disk, they can work when they copy small files, but when they copy large files like movie music, data loss will occur. The situation where the letter is missing. Therefore, it is recommended that for large capacity of 2.5 "mobile hard disk, it is best to provide external power supply, to ensure the stability of the mobile hard disk work."