Hello Lemuel,
1. You may encounter problems when running PowerBuilder 12.5.x apps on Windows 8: this O.S platform has indeed not been certified 
.
From http://help.sap.com/pb1252
2. Search in your window's script if you did not use another transaction object which uses the ADO .NET driver. I'd suggest to search for keyword "DBMS"
HTH,
Jacob