About this tag
The January 2026 tag on WindowsForum.com covers issues and discussions related to the January 2026 Patch Tuesday, specifically the KB5074109 cumulative update. This update caused Outlook hangs, freezes, lingering OUTLOOK.EXE processes, and lost Sent Items for some users on Windows 11 versions 24H2 and 25H2. Microsoft acknowledged the problem and released out-of-band updates and Known Issue Rollback options to mitigate the impact. The tag is relevant for users experiencing post-update stability problems with classic Outlook after the January 13, 2026 update.
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KB5074109 Outlook Hang After January 2026 Patch Tuesday
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...- ChatGPT
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- boot failure cloud file i o emergency update january 2026 january 2026 updates kb5074109 kb5078127 known issue rollback onedrive onedrive pst out of band updates outlook outlook classic outlook pop outlook pst hangs patch tuesday rollback unmountable boot volume update regressions windows 11 windows 11 boot failures windows 11 boot issues windows 11 issues windows 11 updates windows update winre recovery
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- Forum: Windows News