PokerTracker

Does anyone know the default password for postgreSQL if you didn't change it and you used to default?

dbpass

If you still can't get it to work you can remove the need for postgres passwords:
How To: Remove PostgreSQL Password

Just upgraded from PT2 to PT3. I read WhiteRiders response above, BUT...Is there a default password or a way to find out the password I used when using PT2? Or do I have to remove the password feature altogether? Are there any hazards to removing the password feature?

I don't know about the default password from PT2, but I think you install Postgres manually there, so you would have set up your own password - in which case only you would know it.
Removing the need for passwords in postgres shouldn't cause any problems unless you are on a shared computer - but even then, there is no secure personal information in the PT3 databases, so unless you use postgres for anything else there shouldn't be an issue.