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Can't upgrade to Windows 11 Build 26340.9354
So on 8th of Sept Microsoft release the preview build on the windows insider program for the experimental channel build 26340.9354 but no matter what I can't upgrade to this build no matter what I tried to via windows update and it would download and install and ask me to reboot but when I did and the upgrade process start it would always fail and roll back so then I tried running sfc /scannow 3 times and dism to fix any corruptions but still it kept failing then I said well might try with uup dump but the download links are broken on uup dump for this build so then I did a fresh install of windows 11 joined windows insider program and tried to upgrade but it keeps failing with different error codes for example - 0x8007042b I am just now out of ideas what to do next maybe wait for a feature build or something idk I would highly appreciate if you guys leave your comments down bellow
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Because the upgrade rolls back even after a fresh installation, another round of SFC is unlikely to identify the failing setup phase. The code 0x8007042b alone does not name the responsible driver or component. Before another attempt, preserve the setup logs and open the automatically generated SetupDiagResults.xml under Windows, Logs, SetupDiag. Microsoft's SetupDiag guidance says the last reported failure is typically the fatal one when several failures appear. Record that rule, its error, and the setup phase or operation, rather than only the Windows Update message. Include the Panther and Rollback logs from the failed attempt, your current build, hardware model, and Insider channel in a Feedback Hub report. Remove personal information before sharing excerpts publicly. Do not use an unofficial image simply because a download generator failed. The evidence here does not establish a known build-specific fix or justify another clean installation.
