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Both the 32-bit and 64-bit versions of the Microsoft Open Database Connectivity  (ODBC) Administrator tool display both the 32-bit user DSNs and the 64-bit user DSNs in a 64-bit version of the Windows Operating System.

A 64-bit version of the Microsoft Windows Operating System includes the following versions of the ODBC Data Source Administrator tool (Odbcad32.exe):

• The 32-bit version of the Odbcad32.exe file is located in the %systemdrive%\Windows\SysWoW64 folder.
• The 64-bit version of the Odbcad32.exe file is located in the %systemdrive%\Windows\System32 folder.

The Odbcad32.exe file displays the following types of data source names (DSNs):

• System DSNs
• User DSNs

The 32-bit version of the ODBC Administrator tool displays 32-bit system DSNs, 32-bit user DSNs, and 64-bit user DSNs. The 64-bit version of the ODBC Administrator tool displays 64-bit system DSNs, 32-bit user DSNs, and 64-bit user DSNs.

To work around this problem, use the appropriate version of the ODBC Administrator tool. If you build and then run an application as a 32-bit application on a 64-bit operating system, you must create the ODBC data source by using the ODBC Administrator tool in %windir%\SysWOW64\odbcad32.exe. To indicate the type of DSN, you can add “_32″ to the 32-bit user DSNs and “_64″ to the 64-bit user DSNs.

The 64-bit ODBC Administrator tool can be invoked from Control Panel to manage user DSNs and system DSNs that are used by 64-bit processes. On a 64-bit operating system, the 32-bit ODBC Administrator tool is used for Windows on Windows 64 (WOW64) processes. You must directly invoke the 32-bit ODBC Administrator tool from the SysWoW64 folder. You can use the 32-bit ODBC Administrator tool to manage user DSNs and system DSNs that are used by WOW64 processes.