My issue: Launching a game like World of Tanks or some other game that requires D3DX9_43.dll crashes with a cannot be found error
My sub-issue: When attempting to install DirectX Redistributible the error is given "directx an internal system error occurred"
How to fix it:
First you will need the DirectX redistributible: Get it here
Second, if you get the sub issue I had, you will need to modify the registry. Go to:
IF a sub directory called DirectX does not exist, create it. If it already exists, modify the code called "version" to be anything other than what it is. I changed it to "installedversion" and re-ran the installer which then completed successfully.