In 64-bit Windows, there are two ODBC Data Source Administrators: a 32-bit and a 64-bit version.
The ODBC Data Source Administrator that is accessible in the Control Panel, under Administrative Tools, is the same bitness of Windows.
In other words, on 32-bit Windows, it is the 32-bit administrator; on 64-bit Windows, it is the 64-bit administrator.
On 64-bit Windows, you can execute 32-bit and 64-bit applications transparently.
Recent versions of Microsoft Office applications, such as Excel and Access, are available as both 32-bit and 64-bit versions.
Component: CA Datacom Server
To create or modify the 64-bit ODBC Data Source on Windows 64-bit, access the ODBC Data Source Administrator directly from the Start menu or Control Panel.
To create or modify the 32-bit ODBC Data Sources on 64-bit Windows, run the 32-bit ODBC Data Source Administrator from C:\WINDOWS\SysWOW64\odbcad32.exe.
It is important to understand that 64-bit applications can use only 64-bit drivers and 32-bit applications can only use 32-bit drivers.
In a single process, all of the code must be either 32-bit or 64-bit.
Data Source Names (DSN) are likewise separated by bitness since a DSN is defined for a specific driver.
Hence, CA Datacom Server provides both a 32-bit ODBC driver and a 64-bit ODBC driver.
Refer to CA DATACOM TOOLS 15.1 section "Configure Your ODBC Client"
"...Use the Microsoft ODBC Administrator to configure access to CA Datacom®/DB. You must have Administrator access rights to create or modify any ODBC data source, including the default ODBC data source for CA Datacom®. If you do not have Administrator access rights, the data source can be viewed as read-only....
To configure access to CA Datacom®/DB
Open the Data Sources (ODBC) applet under Control Panel/Administrator Tools.
The ODBC Data Source Administrator window appears showing the User DSN tab. Click the System DSN tab... ..."