Please do 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 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 to enable logging and if PokerTracker 4 starts with the same error message send us these files in a
Support Ticket:
--> /Users/{Mac Login}/Library/Application Support/PokerTracker 4/Logs/PokerTracker4.log
--> Your newest 3 or 4 PostgreSQL log files (look for "Mac" in the guide):
Guide: PostgreSQL log files