How to investigate an app that crashes when starting up, using log entries. Includes detailed instructions for one of the simplest adventures in the log, and a summary of code signature errors.
preferences
When an app can only run for a moment, it might seem hard to work out why it crashes. Here are useful clues from the crash log and elsewhere to help you get the app running properly.
Most apps save settings in their preferences file managed by cfprefsd as the UserDefaults server. Here’s how to avoid problems that can cause, and how to use the defaults command.
Two common problems with log: all the censored contents, which can make them meaningless, and the sheer number of entries. How to use logging preferences to tackle them.
If you use Timers in the Clock app a lot, after a while the app may stop working and show a blank view. This is the result of a service hoarding old timers to its property list.
Hundreds of app preferences are hidden away in ~/Library/Preferences and elsewhere. What do they contain, how do they work, and how can they crash an app before it’s even running fully?
First we repaired disk permissions, until SIP made that impossible. Then we reset user permissions until Apple withdrew that advice. Next we ran repairHomePermissions in Recovery. Should you still use that?
Everything you need to know about Containers, Group Containers and Daemon Containers, providing a sandboxed Home folder for apps.
How to get the most out of System Settings, third-party alternatives, and what to do if you still can’t find the setting you need to change.
Repairing permissions has a long history in Mac OS X. The permissions concerned have changed over the years, and it’s no longer what it once was.
The Eclectic Light Company 