Originally posted by adelaarI decided to close down my PC (windows 7) completely to be sure that all eventually running versions would be closed.
Started my PC this morning and tried again.
And YES it opened!!
Now that I know it's a Windows machine your trouble may be a cause other than PokerTracker4, for example security software you run is interfering, perhaps a minor Windows issue, possibly some kind of issue in your PostgreSQL installation, etc. It could even be a harmless case where PostgreSQL had some kind of temporary glitch and rebooting your machine was all that was needed.
But if the problem returns and especially if you're having to reboot frequently to get it working, that's the kind of thing you'd want to use the logging and ticket submission steps in the link I included above - once we can see for ourselves what's causing the trouble we'll be able to get things sorted out.