Microsoft released an emergency out-of-band update for Outlook. The fix addresses significant issues following a recent Windows security patch.

Users reported several problems. Applications became unresponsive, and Outlook experienced hanging. Errors occurred when opening or saving files to cloud storage, including OneDrive. Users also reported missing sent items. Previously downloaded emails were re-downloaded.

The fix targets bugs introduced by the January 13 security update. Reports indicate the bug rendered the email client 'completely unusable' for some users. This cumulative update includes improvements from previous security patches. It is available for various Windows versions.

The market's primary focus remains on the company's upcoming second-quarter earnings report. Microsoft schedules the report for January 28.