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All of the OfficeWriter API objects (ExcelTemplate, ExcelApplication, PowerPointTemplate, PowerPointApplication, WordTemplate, WordApplication) have the output options for saving to disk, saving to memory stream, streaming to user in a page response. The last output option, streaming to the user, has a dependency on System.Web. If you are developing a web application, the reference to System.Web should have been added automatically. For other types of applications, you may need to add this reference.
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