ODBC driver information is stored in subkeys of the Windows registry.
User data sources are stored under the HKEY_CURRENT_USER key and are available only to the current user. System data sources are stored under the HKEY_LOCAL_MACHINE key and can be used by more than one user.
For user data sources, the complete registry key is HKEY_CURRENT_USER\Software\ODBC\ODBC.INI.
The ODBCINST.INI subkey is a subkey of HKEY_LOCAL_MACHINE, which describes the number and types of ODBC drivers installed on the system. The ODBC Data Source Administrator reads the subkey when it invokes the driver’s setup DLL to add or modify a data source for the driver.