Opening reports by double-click
The installer registers the .rpt file type with Windows, so that double-clicking a Crystal Report opens it in ViewerFX for Crystal Reports.
Because the .rpt association is registered at install time, opening a report from Windows — by double-clicking a file, or by opening a .rpt attachment from your email application — opens it in ViewerFX. For the ways to open reports from within the application, see Opening reports.