The system cannot find the optical drive.

Remember to enable the software drive and enable it again in CMOS to speed up the startup. The software drive is available, but not the optical drive. I saw the CD drive detected on the motherboard in CMOS. I think it must be a system problem. I checked the information on the Internet and found that, it is likely that the driver in the ide ata/atapi controller in the Device Manager has a problem. Program The device type in is changed to none. It turns out to be automatic detection. After the transfer mode is DMA (if available), restart the computer and finally find the optical drive. The problem is solved.

Attached relevant information:

Most of the loss of the optical drive is due to the installation of new software or drivers, or the accidental modification of the CMOS settings or config. sys configuration, also because the machine is infected with viruses and so on.

Hardware reasons

1. Reverse data line or damaged data line

Sometimes it is only a small problem, but it will go around a large circle. This shows that to solve the problem, you must be careful and have a keen observation. When the optical drive is lost, check whether the data cable of the optical drive is reversed (Red to red) and whether it is loose. If there is no problem elsewhere, and the data cable of the optical drive is often moved, replace a data cable and try again.

2. Jumper settings conflict with Hard Disk

When the jumper of the optical drive is the same as the hard drive connected to the same data cable, the optical drive cannot be found (or there may be no hard drive). In this case, you only need to change the jumper of the optical drive to a different one. To improve the data transfer rate, it is best to separate the hard disk and the optical drive on two ide interfaces.

3. power cord failure. The power supply is abnormal due to lack of + 5 V voltage or + 5 V voltage.

This is not the case. Because we use too much force When disassembling the optical drive or hard disk, the type D plug of the power supply is loose or the poor plug of the computer working environment is oxidized and rusted, the power supply of the optical drive is not very normal (if it is a hard disk, the sound of the reading disk will be abnormal, and there are a lot of bad sectors on the hard disk surface), the optical drive will not find.

Once, we upgraded the client's IBM host and installed an optical drive. I don't know how to find a new 40-fold Optical Drive. The drive-out box is normal, and it cannot be thought of as a power source. I just want to do something about the software. In the end, there was no more. I picked up the multimeter to test the voltage, and there was no + 5 V voltage. Check the power cord and find that the red line of + 5 V has been broken due to multiple disconnections, but it cannot be seen outside. A small problem has paid the boss's strength.

4. Ide interface corruption

If the drive letter of the optical drive is lost suddenly and the optical drive cannot be used, we can swap the interface between the optical drive and the hard drive. If you find that you can find the optical drive again, but you cannot find the hard drive, it means that the IDE interface for the original optical drive is damaged. If the computer can be started normally after the switch, but there is still no optical drive, this indicates the reason for the optical drive itself. In this case, you can only change the optical drive. There is not much money for an optical drive.

If there is no optical drive in windows, we can also perform DoS (Press F8 to enter DOS after the computer is restarted, rather than DOS under Win98) use the Win98 universal optical drive driver to try to load the optical drive. If it can be loaded successfully, it indicates the reason for the software, and the main reason should be found from the software aspect. Otherwise, we should consider the hardware.

Software reasons

1. Ide driver installation error or conflict with a driver

If we do not correctly install the IDE driver when installing Win98 or 95, or when you open the Device Manager to view the "hard disk controller" after the installation, you will find a yellow exclamation mark, at this time, the drive letter of the optical drive may not be found.

Under normal circumstances, when we enter safe mode, the drive letter of the optical drive does not exist. If you want to use the optical drive in safe mode, you can use the autoexec. BAT and config. attach the drive to the SYS file, so that after you restart the computer, you can use the drive in safe mode.

2. The number of lastdrive settings in the config file is too small.

If we set "lastdrive =?" In the config. SYS file ?" The number is smaller than the actual number of drives. Even if we have installed the optical drive, we cannot see the shadow of the optical drive in "My Computer. In this case, you only need to remove the setting or set it to lastdrive = z.

3. Improper DMA settings

If the optical drive only supports the pio4 standard and does not support the DMA/33 standard, however, we forced the optical drive to use this standard (in the "my computer" attribute, in the "Device Manager", "√" before the DMA of the "set" option in the "CDROM attribute of the optical drive). At this time, the optical drive may be lost, and sometimes the computer may not start properly. Now we can go to the security mode and remove the DMA settings in the CDROM attribute. The Data Transmission Mode Supported by the hard drive or optical drive is displayed in the basic configuration table of the second screen during the startup of the computer.

4. The optical drive is maliciously blocked in the registry.

If the binary value of nodrivers in "My Computer" hkey_current_usersoftwaremicrosoftwindowscur1_vrsionpolicesxplorer is the value of the optical drive. If this option is not specified, you can change the value to 00000000 (01000000 is A, 04000000 is C, and ffffffff is used to hide all the drives ).

Note: The current virus specifically changes the registry so that the drive letter is lost, which makes us format the hard disk and install the system. Some viruses won't cause the drive letter to be lost, but will prohibit the drive from reading the disk. What kind of disc can't be read, but it can be started with the disc.

5. Is the drive of the optical drive correctly installed?

If the driver of the optical drive is not installed with its own driver, the optical drive will also be lost. This situation is generally used to improve the performance of the optical drive, manually add the optical drive accelerator program or other programs found from the network or the disc. The drive of the optical drive is usually included in WIN98 and 95, and does not need to be added. In security mode, you can delete the CDROM option in Device Manager and restart the computer so that the system can find the new hardware and reinstall the drive of the optical drive.

6. Improper CMOS settings

If the transmission mode is set incorrectly in the CMOS settings-the old optical drive that does not support piomode3, piomode4, or DMA/33 will show no optical drive icon in Win98 or 95. In this case, you only need to change the integratedperipherais item, ideprimarymasterpio (or udma) and ideprimaryslavepio (or udma) to auto in CMOS. By the way, if we disable the IDE interface of the corresponding optical drive in CMOS, the optical drive will not be able to find it in any way.

7. Improper use of the virtual Optical Drive

The virtual optical drive can avoid frequent reading of the disc and increase the reading speed, which makes it possible for us to conveniently play the disc game. However, when we do not want to use the virtual optical drive program, we want to uninstall it or install the latest program, but there is an accident that the drive letter of the virtual optical drive is available, but the actual drive letter is gone.