Windows Diagnostic Infrastructure – WDI.DLL
Wdi.dll will be found in your Windows\System32 folder. It installs as part of your Windows Vista operating system. It supports the Windows Diagnostic Infrastructure. This is a new feature of Windows Vista that includes disk diagnostics, memory diagnostics, network diagnostics and troubleshooting, and resource exhaustion diagnostics. You'll find much more detailed information at http://www.microsoft.com/windows/products/windowsvista/features/details/builtindiagnostics.mspx. Microsoft recommends leaving this file in place.
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