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The OfficeWriter 8 installer is available in 64-bit (OfficeWriter-Installer-8.#.#-x64.msi) and 32-bit (OfficeWriter-Installer-8.#.#-x86.msi). The bitness refers to the bitness of the operating system, not the version of SQL Server Reporting Services.
There is a single OfficeWriter installer that that handles installing any configuration of OfficeWriter, regardless of which edition (SE or EE) or components (ExcelWriter, WordWriter, SSRS integration) you have purchased.
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