Code 21: This code means the device has a problem that may be resolved by restarting your computer. To resolve this error code, shut down Windows, turn off your computer, and then turn it back on.

Solution: Restart Computer

Code 22: This code means the device is disabled.

To resolve this error code, enable the device. To do so, follow these steps:

1. Select Start > Setting > Control Panel, then double-click System
2. Select the Device Manager tab
3. Double-click the category for the device you want to enable, and then double-click the device
4. In the Device Usage box, select the check box for the configuration in which you want to enable the device
5. Click OK, and then click Close
6. Shut down Windows, and restart your computer

If this doesn't work, try removing the device in Device Manager, then re-detecting it using the Add New Hardware wizard. If the problem persists, try a clean boot to rule out software interference. If the error persists, contact the hardware manufacturer.

Code 23: This code means the device loader delayed the start of a device and then failed to inform Windows when it was ready to start the device. To resolve this error code, verify the settings for the primary display adapter in Display properties. Try removing the primary and secondary display adapters from Device Manager, and then rebooting to allow Windows to re-enumerate these devices. Verify that the drivers are current and installed correctly.

For devices other than display adapters, follow the recommended solution. If that does not work, try removing the device from Device Manager and using the Add New Hardware wizard to re-detect the device.

Code 24: This code means that the device was not found (for example, it is missing or is not working properly). To resolve this error code, follow the recommended solutions. If the device still does not work, make sure the device is connected to your computer correctly. For example, make sure all cables are correctly installed, or that the adapter cards are properly seated in their slots.

Code 25: This problem typically exists only during the first and second boots after Windows Setup copies all the files. As such, if this code is identified, it is likely an incomplete installation.

To resolve this issue, follow the recommended solution. Reinstalling Windows may be required, depending on whether or not the reboot resolves the issue.

Solution: Restart Computer

Code 26: This code means a device did not load. There may be a problem in the device driver or not all the drivers were installed.

To resolve this error code, follow the recommended solution. If this does not work, use Device Manager to remove the device and then run the Add New Hardware tool in Control Panel. If you continue to receive this error code, check with the hardware's manufacturer or the Microsoft Software Library for an updated driver.

Solution: Restart Computer

Code 27: This code means the portion of the registry describing possible resources for a device does not contain valid entries. For example, the device is marked as configurable, but the configuration information in the .inf file is set to hardwired.

To resolve this error code, use Device Manager to remove the device and then run the Add New Hardware wizard in Control Panel. If the device still does not work, consult the hardware manufacturer for updated drivers or further assistance.

Solution: None

Code 28: This code means the device was not installed completely.

To resolve this issue, follow the recommended solution. If that does not work, try removing the device from Device Manager and using the Add New Hardware wizard to re-detect it. You may need to obtain updated drivers if the error still occurs.

Solution: Reinstall Driver

Code 29: This code means the device has been disabled because the device does not work properly and cannot be made to work properly with Windows.

You may be able to resolve this error code by enabling or disabling the device in the computer's CMOS settings. Windows cannot override this setting. Please contact the computer's manufacturer for assistance with using the computer's CMOS setup program.

Solution: None

Code 30: This code means that an IRQ cannot be shared. This may occur when a PCI/EISA SCSI controller is sharing an IRQ that is also in use by a real-mode device driver that Windows can't change.

To resolve this error code, remove the real-mode driver that is using the same IRQ as this device. The real-mode driver may be loading in the Config.sys or Autoexec.bat file.

Solution: None