To resolve this error message, simply download the latest DirectX files from Microsoft and install it.
Be sure to select the appropriate language for your computer or you could run into problems.
For those of you who want to get ahead of the game, feel free to go download and install this update now even though R5 hasn't been released yet.
As a quick update about the R5 deployment, a few problems have been identified that would have prevented gameservers from going online after updating. Cort and his team are working to resolve the issue now. It seems likely that R5 will roll out this week afterall, hopefully tomorrow as originally planned. Don't worry if it's a bit late though - we'd rather do it right than do it quick
--TE



