------ MS Access, ODBC 64 ----------------------

With MS Office 2010 32-bit installed, it can be a problem installing ODBC-64 support.

Installing requires a redistributable and a registry hack:

http://blog.codefluententities.com/2011/01/20/microsoft-access-database-engine-2010-redistributable/

More info on install:
http://social.msdn.microsoft.com/Forums/en-US/abf34eea-1029-429a-b88e-4671bffcee76/why-cant-32-and-64-bit-access-database-engine-aceoledb-dataproviders-coexist

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Here's a workaround for installing the 64-bit version of the Microsoft Access Database Engine 2010 redistributable on a system with a 32-bit MS Office version installed:

Check the 64-bit registry key "HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Office\14.0\Common\FilesPaths" before installing the 64-bit version of the Microsoft Access Database Engine 2010 redistributable.
If it does not contain the "mso.dll" registry value, then you will need to rename or delete the value after installing the 64-bit version of the Microsoft Access Database Engine 2010 redistributable on a system with a 32-bit version of MS Office installed.
Use the "/passive" command line parameter to install the redistributable, e.g. "C:\directory path\AccessDatabaseEngine_x64.exe" /passive
Delete or rename the "mso.dll" registry value, which contains the path to the 64-bit version of MSO.DLL (and should not be used by 32-bit MS Office versions).
Now you can start a 32-bit MS Office application without the "re-configuring" issue.
Note that the "mso.dll" registry value will already be present if a 64-bit version of MS Office is installed. In this case the value should not be deleted or renamed.

Also if you do not want to use the "/passive" command line parameter you can edit the AceRedist.msi file to remove the MS Office architecture check:

download and install Microsoft Orca:
http://msdn.microsoft.com/en-us/library/windows/desktop/aa370557(v=vs.85).aspx
unzip the AccessDatabaseEngine.exe or AccessDatabaseEngine_x64.exe file
open the AceRedist.msi file in Orca
search for two table rows containing the "CheckOfficeArchitecture" action and drop these rows
save the updated AceRedist.msi file
you can now use this file to install the Microsoft Access Database Engine 2010 redistributable on a system where a "conflicting" version of MS Office is installed (e.g. 64-bit version on system with 32-bit MS Office version)
Make sure that you rename the "mso.dll" registry value as explained above (if needed)
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Then, setting up the DSNs can be confusing, because both 32 and 64 bit DSNs are visible in both the 32 and 64 ODBC configuration:
https://blogs.msdn.com/b/farukcelik/archive/2008/10/17/why-my-32-bit-applications-cannot-see-the-odbc-dsns-that-i-created-on-my-64-bit-machine.aspx?Redirected=true

The procedure to set up a 64 bit ODBC DSN:
Open 64 bit odbcad32.exe (c:\windows\system)
Create new
IF IT CRASHES when Selecting the file, then finish the DSN config without
selecting the file.  Then Open the 32 bit odbcad32.exe and finish it there.

To set up 32 bit DSN, you must open c:\windows\SysWOW64\odbcad32.exe

--------------- END ODBC ----------------