Regardless of whether this is a safe file or malicious, what it most certainly isn't is a genuine, digitally signed, earlier version of a DirectX file from Microsoft. Now hopefully this file may well be a custom-written hack by a helpful programmer who has discovered a way to fix performance issues, but there appears very little explanation from the author on exactly what this file does, how it does it and why he wrote it in the first place. I'm fairly certain that earlier d3d9.dll files came in at over 1Mb. This dubious d3d9.dll file also has an alarmingly small file size at 104kb. This tells me it's not a genuine Microsoft file. Now right click on this d3d9.dll file that people are downloading to fix their problems and click on Details and you'll find most of the fields are blank apart from Type, Size and Date Modified and it has no tab for Digital Signature. Any digitally signed files will also have an extra tab labelled Digital Signature.

The Product Name field for example would contain Microsoft DirectX for Windows, while the Copyright field would contain Copyright Microsoft Corp 1994-2007. Right click on any genuine Microsoft DirectX dll file and then click on the Details tab and you will find that narly all the Description fields contain information in the Value fields. Claims are being made that it's just an earlier version of a DirectX 9 dll but all genuine Microsoft DirectX dll files are digitally signed by Microsoft.

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