Using 64-bit Merge Modules

A 64-bit merge module has any of the characteristics identified in this this topic.

The merge module contains at least one component that has been compiled for 64-bit operating systems.
The merge module contains no 64-bit components, but is intended for use only with 64-bit Windows Installer packages.

Merge modules can be used as follows:

A 64-bit merge module can be merged into a 64-bit Windows Installer package. The Template Summary properties in the merge module and in the Windows Installer package must be set to the same type of 64-bit processor. A x64 merge module can be merged only into x64 packages and an Intel64 merge module can be merged only into Intel64 packages.
A 32-bit merge module can be merged into 32-bit or 64-bit Windows Installer packages.
A 64-bit merge module can be merged into a 64-bit package on a 32-bit operating system.

Adhere to the following when authoring a 64-bit merge module:

Use the same general procedure as when authoring 32-bit merge modules. For information, see About Merge Modules and Authoring Merge Modules.
You must set the Template Summary property with the Intel64 value if running an Intel64 system. You must set the Template Summary property with the x64 value if running an x64 system. For information see Merge Module Summary Information Stream Reference.
When both 32-bit and 64-bit merge modules exist for the same component, it is recommended that the modules have different signatures. This will enable a package to contain both versions of the component.

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