Broke 0.7 Vistas Fixed officially acknowledged Mar 9, 2021 their #21 worst broke on record

Printing? Congratulations, you've won a bluescreen

KB5000802 caused APC_INDEX_MISMATCH bluescreens when printing with Type 3 drivers

↳ caused by KB5000802 ↗

↳ fixed_by KB5001649 ↗

The market's verdict: +3.3% on MSFT in the week after.

Status: Fixed. Working as intended, eventually.

What actually happened

The March 9, 2021 cumulative updates bluescreened Windows 10 the moment it tried to print, as long as the printer used a Type 3 driver. That covers about half the laser printers on the planet. Microsoft shipped an emergency fix within the week. Until then, the official advice was to uninstall the update or swap printer drivers. On a Tuesday. In a print shop.

This one is officially acknowledged.

Were you affected? Unbreak it

Install the out-of-band fix ↗

Windows Update → Check for updates, or download KB 5001649 from catalog.update.microsoft.com.

Or uninstall the offending update ↗

wusa /uninstall /kb:5000802 /quiet /norestart

Timeline

Mar 9, 2021 Confirmed First reports came in.
Mar 15, 2021 Fixed Emergency fix shipped, four days later.