As this has caused me a bit of pain recently I thought I’d compile everything you need to know about finding that missing window in civil. For me it was the panorama window / elevation editor commands that had gone missing but it applies to most windows.
For the panorama window you can check here
“You try to open the Panorama window but the Panorama window does not
display, and the current command ends.
Solution
Your drawing window should not be maximized when you use Alignment and
Profile Grid Views. Commands such as Create by Layout and Edit (associated
with Alignments and Profiles),use the Panorama window to display the Grid
View for editing content.
If the Panorama window does not display, resize the drawing window so that
it is not maximized, and run the command again.
If the drawing window is maximized and you try to open the Panorama window
in a docked state, the current command ends and the Panorama window is not
displayed. To avoid this issue, follow these guidelines:
If the drawing window is maximized, the Panorama window must be floating,
not docked.
If the drawing window is not maximized, the Panorama window can be docked”
If this has failed you the chances are its appearing off-screen , which has the following solutions
Open this with word and you find this and you can adjust its position of the window back on the screen. I believe this coordinates are the distance from the top left of the AutoCAD application window. (this did not work for me, I might have been adjusting the wrong one)
You might also be able to set the windows to be docked left or right and they should appear again but I’m not super confident tinkering with my text files.
If that doesn’t work id try repairing the install and crying you probably have a more serious issue.
Hope this helps!
This was absolutely the case on my end using Civil3D 2023. Using multiple monitors, I ended up losing the Panorama window. Two keys: