A routine January Patch Tuesday rollup (KB5074109) accidentally left parts of Microsoft’s classic Outlook experience unstable for a measurable number of users, triggering freezes, lingering OUTLOOK.EXE processes, lost Sent Items and a rapid sequence of follow‑up fixes and mitigations from...
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windows 11
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Microsoft's first cumulative Windows 11 update of 2026 — delivered as KB5074109 on January 13 — has left a broad trail of disruption: critical security fixes were installed, but several high-impact regressions followed, forcing Microsoft into rapid damage control with out‑of‑band patches and...
boot failure
boot failures
boot issues
classic outlook
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emergency update
enterprise it
january2026updates
kb5074109
known issue rollback
known issues
onedrive
out of band updates
outlook
outlook classic
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security patches
system regressions
unmountable boot volume
windows 11
windows 11 issues
windows 11 updates
windows updates
winre
winre recovery