If you are using Windows XP or Windows Vista, in case you might have a Windows PC for a long time, you might be facing a problem related to the Windows asking you to install the Update 929399 repeatedly and it does not install automatically. This problem is a known issue and is related to the DRM functionality related to digital media on your Windows PC. If you download DRM enabled music from some service or use a media-device which uses DRM music, then in that case there maybe problems with subscription servers failing to extract music from such filed using your Windows PC and this is the reason why you might be getting this repeated prompt to install this update.
The cause of this problem as per the Microsoft Official support page is:
Subscription services, such as sites that provide music downloads, cannot extract metering data from some portable devices that support metering. This problem causes difficulty when you try to listen to downloaded content.
This problem occurs when the services try to synchronize metering data on a Windows XP-based or on a Windows Vista-based client computer that is running the Microsoft Windows Media Format 11 Software Development Kit (SDK). The system prompts you to download a security component update.
Now there are many suggested ways to fix this problem, but we will tell you the most convenient and easy to use way. You can manually download and install the update from Microsoft Official website and get rid of this problem.
Complete download procedure is mentioned below:
To download this update from the Microsoft Download Center Web page, follow this step:
Click Download, and then click Run or click Open to install the update.
Note Before you can download this update from the Microsoft Download Center, you may be prompted to validate Windows. If the Download option is not available, you must validate Windows.
To validate Windows, click Continue, and follow the instructions on the Microsoft Download Center Web page. This online validation process is quick and easy. After you validate Windows, you can download and install the update.
Download the update for 32-bit versions of windows for an x86-based computer
The following files are available for download from the Microsoft download center:
Microsoft windows media format 11 SDK for windows vista on x86-based computers
Microsoft windows media format 11 SDK for windows vista on x64-based computers
Microsoft windows media format 11 SDK for windows XP on x86-based computers
NOTE: This hotfix does not have a 64-bit version for windows XP. This hotfix package applies the 32-bit version of this hotfix on the 64-bit version of windows XP.
Microsoft windows media format 11 SDK for windows XP on x64-based computers
via – Microsoft Support