Layout locked after adding viewport

[toddhawley]

Hello,

First off let me say that I am using Civil3D 2020 and I am using Sheetset Manager (SSM). The issue I am experiencing is best described with an example.  I have created a new sheet in SSM.  I open the layout and I add a viewport from another drawing via the "Model Views" tab in SSM.  I then add a second view to the layout.  Upon adding the second view, the data in the first view disappears.   So I decide to delete the first viewpoint and simply add it back. (This has worked in the past)  Except I cannot delete the first viewport or modify anything on the layout.  I can select objects but cannot change or delete them.  This locking behavior is what I'm primarily trying to solve.  The disappearing data in the viewport is a separate problem. (Which i suppose I should make a separate post unless the two are related)  I have experienced this behavior when adding anything to the layout.  For instance, add a north arrow linked to the viewport, everything is locked.  Execute the clip viewport function, everything is locked. In most cases I am allowed one action and then the layout is locked. I can however delete my title block which is an xref in my sheetset template dwt.  I can also close the drawing containing the layout and reopen and then I can continue to work however if I executed one of the examples mentioned above the layout would be locked again. I also attempted making these edits in vanilla AutoCAD with the same results.  While doing so I looked at the properties dialog while the viewport was selected.  I noticed that "Display locked" was set to "No."  I attempted to change it and an error dialog popped up, "Object was open for read." The strange thing is in the same viewport that is locked I can switch to model mode and delete the contents inside the viewport but not the viewport itself. 

As additional info that might be relevant, my workflow involves having all linetypes, lineweights, colors, etc governed by the modelspace drawing rather than the layout.  In an attempt to have that functionality I have set the following acad variables:

VISRETAIN = 0

XREFOVERRIDE = 0

VPLAYEROVERRIDESMODE = 0

Also to add questions I received in the Acad forum:

Yes Civil is full up to date.

The problem occurs on all drawings.

The problem also occurs when replacing my sheetset template with a blank acad.dwt and creating a new sheet.

MAXACTVP = 64

I have found many examples of behavior that is similar in the forum but none solved my problem. 

If this is a duplicate post I apologize.  I would be grateful for any suggestions. 

[toddhawley]

I have determined that the issue is the result of adding named views to a layout from multiple sources.  That is for instance, I have three separate drawings for plan view, profile, and legend.  I can add multiple views from a single drawing with no problem.  Adding views from multiple drawings to the same layout causes the issues mentioned above. 

[toddhawley · Accepted solution]

EDIT:

After some more experimentation, it seems that the presents of Civil3D specific objects may be the source of the problem.  I had xrefs that included Civil3D alignments and profiles.  I converted those drawings to vanilla AutoCAD using explode and the exportToAutocad command.  This seemingly fixed both problems I was experiencing.  This is good for the current project which is small however I really liked being able to leave my profiles and alignments dynamic so that revision was easier. Of course I have to acknowledge that by converting to vanilla I'm also remove any potential issues that may simply be an issue with my Civil3D template and not necessarily Civil3D objects so there's that.  If anyone has any ideas as to why Civil objects might be responsible I would appreciate it.  It occurred to me that perhaps converting to vanilla cad is what everyone does at the publish stage especially for performance reasons.  I would be interested to hear if this is or is not the case.