Windows 11 shutdown bug forces Microsoft into out-of-band damage control

Microsoft issued an out-of-band Windows 11 update (KB5077797) after the January Patch Tuesday cumulative update caused serious regressions — most notably systems failing to shut down or hibernate, Remote Desktop credential prompt loops preventing sign-in, and reports of Outlook POP profile hangs. The emergency fix restores expected shutdown/hibernate behavior and addresses the RDP authentication issue; Microsoft acknowledged the problems were introduced by the January update and advised affected users to install the OOB patch.