So long as you right click on the edge (border) of the drawing or on something that is selectable in the drawing, you should always have the option to 'Open Source View'.
If you just right click on the background space then you won't get this option unless your 'Quick Select' (magnet) is active.
If you are sure that all of the drawing settings are the same then it must be the view settings.
If you are manually opening a view from the Project Map then you manually choose the pen set, renovation filter and graphic override (plus other options) that can affect how the view looks.
Opening a view from the View Map will open it with the same settings the view was saved with - this is the same as right clicking in the layout and opening with source view.
Barry.
One of the forum moderators.
Versions 6.5 to 27
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