When you try to create a DVD by using Windows DVD Maker in Windows 7, you receive an error message that resembles the following:
Invalid Class String
This issue may occur because some registry keys were damaged during the installation of DirectShow drivers.
Almost all media applications install their own DirectShow drivers. Many different driver packages are available on the Internet, and some registry keys might become damaged during driver installation.
Important This section, method, or task contains steps that tell you how to modify the registry. However, serious problems might occur if you modify the registry incorrectly. Therefore, make sure that you follow these steps carefully. For added protection, back up the registry before you modify it. Then, you can restore the registry if a problem occurs. For more information about how to back up and restore the registry, click the following article number to view the article in the Microsoft Knowledge Base:
322756 How to back up and restore the registry in Windows
To resolve this problem, use one of the following methods:
Method 1: Delete two registry keys
Click Start , and then type cmd in the search box.
Right-click cmd.exe, and then click Run as administrator.
In the command prompt, type the following commands. Press Enter after each command.