Hi isaactaz,
· What program/game are you trying to install on your computer?
· Which version of the operating system are you currently running?
Based on my research, SDL.dll ("Simple DirectMedia Layer") is a file that should come with the game itself and be in the game's folder.
If you’ve trouble installing or running a game properly on your computer, the DirectX Diagnostic Tool can help you pinpoint the source.
Method 1: Diagnosing basic problems with DirectX
http://windows.microsoft.com/en-US/windows7/Diagnosing-basic-problems-with-DirectX
Method 2: Download and install the latest DirectX
Hope this information is helpful and let me know if you need any further assistance.
Mouneshwar R – Microsoft Support
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