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january 2026
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.
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...
boot failure
cloud file i o
emergency update
january2026january2026 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