There could be many reasons why PostgreSQL (the program where PokerTracker 4 stores your poker data) isn't running. Is this a new install or was everything working correctly until now?
If this is a new install did PokerTracker 4 ask if it could install PostgreSQL for you? If so did you notice if the PostgreSQL install completed successfully?
If this is an existing install have you made any changes recently? Have you done something recently to PostgreSQL such as trying to partially uninstall it, changing permissions on any of its folders, shutting down your computer unexpectedly while the database was in use, or maybe deleting the "postgres" user from your Mac login screen? Do you see PostgreSQL in your Applications folder?
Or maybe you have transferred data from another machine using 'Time Machine' or another cloning tool?
If nothing has changed and everything was OK the previous time you started PokerTracker 4 then try this:
1. Confirm where your PostgreSQL is, probably here:
/Library/PostgreSQL/x.y
"x.y" will be two numbers such as "8.4", "9.0", etc.
2. Open a terminal, probably in "Utilities". In the terminal window copy/paste this:
sudo rm /Library/PostgreSQL/x.y/data/postmaster.pid
Substitute the "x.y" in that command with the numbers you noted in #1.
You want to delete "postmaster.pid" so answer "y" if the command finds it.
3. Next reboot, press/hold the "Alt/Option" key while starting PokerTracker 4 and click through any messages. Only start PokerTracker 4 once even if nothing appears.
If PokerTracker 4 starts you should be fine otherwise attach these files to a
Support Ticket along with any relevant answers to the questions I asked above:
--> /Users/{Mac Login}/Library/Application Support/PokerTracker 4/Logs/PokerTracker4.log
--> The newest 3 or 4 PostgreSQL log files (look for "Mac" in the guide):
Guide: PostgreSQL log files