At some point, you will encouter an error message from your computer. On PC’s running on Windows XP, error messages are very vague. But due to the fact that there is an error message, you should assume that something is wrong with your PC. These error messages occur while the System is just starting up, while you are using an applicationor while you are trying to obtain access to a hardware device such as a flash disk. Errors are frequently caused by malwares such as viruses, trojan horses, worms and spywares that intend to destroy your PC’s system. Some registry problems may also cause these errors.

Preventing errors on your PC is quite a simple, but time consuming task.  The first thing you have to do is to install an anti-virus and an anti-spyware. This will defend you against most malwares. Be sure to update these applications regularly. Use these tools to scan your computer regularly. They will check for malwares and try to delete it so that the malware would no longer be able to harm your system. Installing a firewall might also be a good idea. Firewalls defend you from other malwares and intrusions. You might also want to use a registry cleaner to make sure that the registry is working well. You have to make use of these various applications to make sure that your PC is well defended. But in the case of an already existing error, these applications are rendered useless.

When an eror such as Code 39 Error exists on your system, what you should do is to fix it immediately. Code 39 error is a error on your hardware device. If you can’t see and access your CD/DVD rom drive, then this error is the cause of it. To see the error message, go to the device manager. You can go there by right-clicking My Computer, then choosing properties. Select the Hardware tab and click the Device manager button. Your CD/DVD rom drive should have a yellow triangle with an exclamation mark beside it.  This indicates the error on  your CD/DVD rom drive. To fix this problem, you can first try to update the driver. Right click on the CD/DVD rom drive and choose Update Driver. You should follow the machine instructions in order to successfully complete the update. You should restart the PC afterwards.

When updating the driver does not fix anything, it must mean that there is a problem with the registry. You should then edit the registry in order to fix the Code 39 error. To edit the registry, you must do the following steps:

1. Exit all the applications running
2. Click the Start button and choose Run
3. type Regedit and press enter
4. Go to HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Class\{4D36E965-E325-11CE-BFC1-08002BE10318}
5. If you see any of the following under this key, remove it immediately:
   UpperFilters
   LoweFilters.bak
   LoweFilters
   UpperFilters.bak
6. Exit the Registry Editor
7. Restart your PC.

Once you have done these steps, you should be able to see and access the CD/DVD rom drive.