Insider Windows Update Device stuck on build 26220.6972 — no updates since Oct 2025

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Device stuck on build 26220.6972 — no updates since Aug/Oct 2025

My Windows 11 Insider device is stuck on build 26220.6972 and has not received any cumulative or security updates since October 2025. The Insider Program page shows I’m enrolled, but there is no channel selector, and the WindowsSelfHost registry key is missing. WindowsUpdate.log shows no flighting activity, and the device does not detect new public releases or Insider builds.

I believe the Insider backend is corrupted and Windows Update is unable to use either the public or Insider servicing channels. I need assistance restoring normal update functionality without performing a full reinstall.

⭐ Technical Version (for engineering‑level support)

Subject: Insider backend corruption causing complete Windows Update servicing failure

Summary: Device stuck on Insider build 26220.6972 (ge_release) with no cumulative updates since Oct 2025. Insider UI present but backend flighting configuration appears to be missing.
Windows Update unable to access either Insider or public servicing channels.

Technical details:

Insider Program UI shows enrollment but no channel selector and no linked Microsoft account.
The entire WindowsSelfHost registry structure is missing (root key and all subkeys).
WindowsUpdate.log contains no flighting metadata, no applicability rules, and no Insider targeting entries.
Update history shows no cumulative updates, servicing stack updates, or .NET updates since Oct 2025.
Device does not detect new public releases or Insider builds.
“Unenroll this device when the next version of Windows releases” toggle is ON, but unenrollment cannot occur because the device cannot detect new releases.
Experience Pack updates continue (via separate pipeline), confirming partial servicing functionality.
System appears stuck in a UI‑enrolled but backend‑detached Insider state, preventing both Insider and public updates.

Impact: Windows Update servicing is non‑functional. Device is missing ~8 months of quality patches and cumulative updates. I cannot receive Insider builds or public releases. Cannot automatically unenroll at next major release.

Request: Guidance on restoring Windows Update servicing and Insider backend without a full OS reinstall. Specifically need assistance re‑establishing flighting configuration or safely resetting Insider enrollment.

System info: