The file describes properties, such as the data source name and directory, the connection driver, the server address, user ID, and a password. It is used by ODBC drivers to connect to a specified database, such as a SQL Server or Microsoft Access. DSN files are typically stored as plain text files.
In XP, I believe the default location for file DSN's was C: Program Files Common Files ODBC Data Sources. In Windows 7, when running odbcad32.exe and creating a file DSN, the default location that it's saved to is My Documents. In fact, the ODBC directory no longer exists under Common Files. This seems counter intuitive for a file that is (or was) considered accessible among all users of a computer in the past. You'd think that if Microsoft were going to change the default path, that it would be to the Public Documents folder so that the expected functionality of 'accessible by all users' would still hold true. Is there any documentation from Microsoft on where the default File DSN location should reside on a local drive in Windows 7 (and perhaps Vista), and why this behavior has changed? It almost seems as if Microsoft is discouraging use of File DSN's.