Because PT3 works nothing like PT2 does. I don't know what else would be causing these errors with the ODBC drivers, this is a problem with your computer, not the software. Try reinstalling these Microsoft Data Access Drivers (MDAC)...
http://www.microsoft.com/downloads/deta ... laylang=enAlso, I just looked at the code. You would only get an error like this if your default database is an Access database, not PostgreSQL. Are you sure you have converted your PT2 to PostgreSQL? Using the registry editor again, go to...
HKEY_LOCAL_MACHINE\SOFTWARE\PTrack
And under that you should see entries like 2DB1, 2DB2, 2DB3, etc. Scroll through these entries, you will see on the right side a value "Default". If it's a 1 then that's your default database PT2 is trying to open. How many of these "2BBxx" values do you have and for each one, what is the value of the "Filename" field. For an Access database, it will be an actual file name, for PostgreSQL, it will just be the name of the database.