When you upgrade a project from a previous version of Revit, the sun setting that was saved with the project is applied to the upgraded project, unless the project was saved with a named sun setting, shadows off, and the Use sun position for shaded views option cleared (deselected). In this case, the saved settings cannot be applied due to changes in the software; therefore, the <In-session, Lighting> setting is applied, as this setting most closely emulates the lighting conditions produced by the previous settings. If your named sun setting is no longer selected after you upgrade the project, you can select it in the Sun Settings dialog under Presets.
When the Lighting mode is in effect and Relative to View is selected, the sun path does not display. A dialog displays options for specifying sun settings:
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