Crew Chief continuously logs all kinds of infomation in its "Console window" and when Crew Chief exits it saves it all in a file in the folder <Documents>\CrewChiefV4\debugLogs (for example c:\users\Documents\<your name>\CrewChiefV4\debugLogs).  Each one has a timestamp in the name which is the date and time when it was saved (for example c:\users\Documents\<your name>\CrewChiefV4\debugLogs\console_2022_03_23-20-12-26.txt, year_month_day-hour-minute-second). It keeps the latest 25 files, deleting older ones.

You can also save a file at any time by right clicking on the Console window.

If Crew Chief isn't working for you then the most important thing is to upload the log file that was saved after you saw a problem to either the forum, Discord or to the confidential email address

If Crew Chief crashes the log file won't be saved but a previous one may help.