How to Troubleshoot Cdrom.sys

If cdrom.sys is corrupt, the computer won't detect a CD when you insert it in the CD-ROM drive.

Cdrom.sys is the CD-ROM driver for Windows. Virus infections, file corruption and system upgrades can cause cdrom.sys to stop functioning, which in turn prevents the operating system from detecting and reading CDs. Device Manager, a built-in application used to manage devices, will display a "Code 31," "Code 32" or "Code 19" message in the CD-ROM device properties if the computer detects a problem with cdrom.sys. To troubleshoot cdrom.sys, check the computer for infections, use System File Checker to replace a corrupt cdrom.sys, and delete the upper and lower filters from the Windows Registry.

Instructions

1. Restart the computer. Press "F8" at startup to go to Windows Advanced Boot Options. Select "Safe Mode" from the options, then press "Enter."

2. Log in to Windows Safe Mode. Run an anti-virus scan on the computer to see if a virus or other infection has corrupted Cdrom.sys. If the anti-virus scanner detects an infection, follow the on-screen instructions to clean or replace the file.

3. Restart the computer and log back in to Windows. Click "Start." Go to "All Programs," then to "Accessories." Right-click "Command Prompt."

4. Select "Run As Administrator" from the context menu. Insert your Windows 7 DVD into the disc drive, if possible, then input "sfc /scannow" into the command-line interface.

5. Press "Enter" to run System File Checker on the computer. If SFC detects a problem with Cdrom.sys, it will replace the file from the Windows 7 DVD or i386 folder on the hard drive.

6. Restart the computer if prompted. Test the CD-ROM drive. If the Cdrom.sys error reoccurs, or if the Device Manager displays the Code 31, Code 32 or Code 19 errors, click "Start."

7. Type "regedit" into the search box. Right-click "regedit" from the results, then select "Run As Administrator" from the context menu.

8. Expand "HKEY_LOCAL_MACHINE," "SYSTEM," "CurrentControlSet," "Control," then "Class." Click "{4D36E965-E325-11CE-BFC1-08002BE10318}." Right-click "UpperFilters."

9. Select "Delete" from the context menu. Click "Yes" to remove the value from the Windows Registry. Repeat the steps for "LowerFilters." Restart the computer after removing both keys.

10. Retest the CD-ROM drive to determine if further troubleshooting of Cdrom.sys is required. If the computer is still unable to detect CDs, go to Device Manager via the Start Menu.

11. Expand "DVD/CD-ROM Drives." Right-click the CD-ROM drive, then click "Uninstall." Restart the computer to reinstall the CD-ROM drivers to the computer.

References

• Microsoft Support: Cannot Access CD-ROM and "Code 31" Error Message in Device Manager After You Remove Adaptec Easy CD Creator From Your Computer
• Microsoft Windows XP: System File Checker (SFC)