Current downloadable version of SetupDiag: 1.6.1.0
“SetupDiag in Windows 10, version 2004 and later
With the release of Windows 10, version 2004, SetupDiag is included with Windows Setup.
During the upgrade process, Windows Setup will extract all its sources files to the %SystemDrive%$Windows.~bt\Sources directory. With Windows 10, version 2004 and later, setupdiag.exe is also installed to this directory. If there is an issue with the upgrade, SetupDiag will automatically run to determine the cause of the failure.
When run by Windows Setup, the following parameters are used:
/ZipLogs:False
/Format:xml
/Output:%windir%\logs\SetupDiag\SetupDiagResults.xml
/RegPath:HKEY_LOCAL_MACHINE\SYSTEM\Setup\SetupDiag\Results
The resulting SetupDiag analysis can be found at %WinDir%\Logs\SetupDiag\SetupDiagResults.xml and in the registry under HKLM\SYSTEM\Setup\SetupDiag\Results.
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