At last there’s a fix. Millions of Outlook users been plagued with failed restarts and missing emails since Microsoft released its mandatory January security updates. Now the company has confirmed a new emergency update to put things right.
Microsoft was reasonably quick to admit that “Classic Outlook profiles with POP accounts and PSTs hang after Windows updates on January 13, 2026.” Also warning that there’s no fix, but more guidance would be coming soon.
This has been serious. Neowin reported that “Microsoft makes Outlook ‘completely unusable’ as Windows 11 25H2/24H2 update breaks it.” Those issues include “random hangs and freezes, unsaved email progresses, and more.”
Microsoft now says the issue is more specific. “Some applications became unresponsive or encountered unexpected errors when opening files from or saving files to cloud-based storage, such as OneDrive or Dropbox. In certain Outlook configurations that store PST files on OneDrive, Outlook may hang and fail to reopen unless the process is terminated or the system is restarted.” And affected users would also see “missing sent Items or previously downloaded emails being re‑downloaded.”
The emergency update is available for Windows 11 25H2, Windows 11 23H2 (albeit you should move away from this now, and Windows 10.
This emergency update follows last week’s emergency update, which fixed a failure to shut down flaw and, per Windows Latest, “a much more widespread” remote desktop login failure affecting 24H2 and 25H2.”
Microsoft says the new updates are “cumulative and include security fixes and improvements from the January 13, 2026, security update and the out-of-band update from January 17, 2026.” If everything is working fine and you have installed January’s security fixes, you don’t need to update again. But for millions, that’s not the case.