A computer that does not start, stops responding, or began to misbehave after an update: stop codes and crash logs, safe mode, driver rollback, and the built-in repair tools you run to find out what changed.
Common failure modes
- An update installed and the machine unstable ever since
- A driver rolled forward with no record of the version that worked
- A stop code seen once, cleared, and never written down
- A startup fault never isolated, because safe mode was never tried
- A repair started before any backup existed
Procedures
- How to find out why a laptop runs hot and the fan is loud
- How to run First Aid in Disk Utility to fix disk errors on a Mac
- How to boot a Mac in safe mode when it won't start up properly
- How to find the stop code after a blue screen in Windows, and what the code actually means
- How to go back to the previous driver in Windows when a driver update breaks a device
Where this stops
Component-level hardware repair and data recovery from a failing disk need a specialist. A page that reaches that point says so and stops.