While working in a drawing (second time this has happened). Doing site grading the contour layer and lines become unlsectable. I isolate the layer and they disappear. I can't select edit anything...
HELP... I have purged everything out of the drawing and I still can't get the lines to show up. If I touch them and then Regen they disappear entirely.
Welcome to the Forums, but I'm afraid I [one of the comparatively few who can still open a drawing in 2004] have no idea what the problem could be.
The only situation in which I've seen things visible but unselectable is that when Layer 0 is turned off or frozen, things on the Defpoints Layer are visible but cannot be selected or object-snapped to. Your drawing didn't even contain a Defpoints Layer, so in case that had anything to do with it, I drew a Dimension to make one, but that didn't fix it.
I drew something new on one of those affected Layers, and I could select and snap to that, but still not to other things.
I wondered whether they might all be part of an Image or something, but turning ImageFrame on didn't reveal anything, and there are large quantities of Polylines and Mtext objects listed by DBLIST, so they are their own things. Some, but not all, of the elevation numbers and the boxes around them on the major-contours Layer, and one piece of contour on that Layer, can be selected, so it doesn't seem to be a characteristic of the Layers, but rather of the objects. But I'm not aware of any selectability option for objects in 2004.
I found that things are pretty far from the origin [in the range of 600000 to 700000 drawing units], and wondered whether that could have any effect. I found I could use editing commands on things by giving entity names, so I did a quick Lisp function to Move everything a lot closer to the origin, and it did that part successfully, but that didn't fix the problems you describe.
Did this come from someone else, drawn in a more recent version, or converted from some different program? I'd be interested in whether it has the same problem when opened in a newer version [which I can't try here, but can elsewhere later, with 2015].
Command FLATTEN, type in ALL answer NO and enter.
That makes things selectable, but it does, after all, Flatten everything. The original contour lines are actually at different elevations as these things are commonly drawn, and all of that is lost by Flattening. I hope someone knows of a way to get around the bug that retains their elevations, but I don't have anything else to suggest.
I found something pretty easy that works for me: Use COPYCLIP or COPYBASE, give it ALL for a selection, then open a new drawing and use PASTECLIP or PASTEORIG [I didn't try it, but I assume PASTEBLOCK would also work] to bring it in. In the new drawing, I am able to select and otherwise work with the pasted-in content, and different elevations are retained, unlike with the Flatten approach.
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