Some of the users in our Windows 7 Forum reported a strange problem after upgrading to Windows 7. Some of the connected DVD drives where not recognized by Windows 7. The devices where listed in the device manager with a yellow exclamation mark displaying that there were problems with digital signings.
Windows cannot verify the digital signature for the drivers required for this device. A recent hardware or software change might have installed a file that is signed incorrectly or damaged, or that might be malicious software from an unknown source. (Code 52)
The workaround that helped all users in the forum was to press F8 during boot to turn of digital signing. This would load the drivers for the drives and they could be used normally. This is on the other hand not a perfect solution. To fix the problem that dvd drives are not recognized in Windows 7 permanently do the following:
1. Press Windows R, type regedit and press enter.
2. Open the Registry key
3. In the right pane, right-click UpperFilters, and then click Delete.
4. Click Yes to confirm the removal of the UpperFilters registry entry.
5. In the right pane, right-click LowerFilters, and then click Delete.
6. Click Yes to confirm the removal of the LowerFilters registry entry.
7. Exit Registry Editor, and then restart the computer.
Note After you remove the UpperFilters registry entry and the LowerFilters registry entry, you may lose functionality in certain programs such as CD recording programs. In this scenario, you must reinstall any affected programs. If the problem recurs, contact the program vendor to determine whether an update is available for the program.
Click on Start -> All Programs -> Accessories -> Right click Command Prompt -> Run as administrator.
Paste the following line and hit enter afterwards
bcdedit /set loadoptions DDISABLE_INTEGRITY_CHECKS
This should solve the problem of DVD drives not being recognized in Windows 7.