Topic Title

I have two files in a project with several files that have multiple entities stacked on top of each other. Somehow there has been multiple copies of the entire file saved on top of one another. I want to erase all the copies but one for obvious reasons. I have tried the "hide" feature in 3D menu but when I select "begin" it never accomplishes anything. I finally have to just close and reopen. I can't use the mask feature because all entities that are stacked are the same due to being copies. I have no idea how the files got that way. The files are a preliminary floor plan and elevations with lots of entities per copy because I was almost completely done with them. I have other files in the same job that don't have the multiple copies on top of each other. Can anyone help with this or will I have to just redraw?

That's a tough one.
You might be lucky if when copied they were a group. then you could do a delete by group the number of times you have multiples. Just undo the last erase when they have all gone away.

For lines there is a way to do this: layer by layer do a Hidden Line Removal (HLR) and Save the Image to a layer file. Then Load that layer file; deleting the existing multiple copes in the process.

For any arcs or text, I would move one copy to another layer first, and then erase using Mask to get rid of all the other copies at once.

If you have sessions or backup files you could try finding a older version that doesn't have the duplicates, odds are it wouldn't be too out of date because obviously you would have noticed the duplicate work, and then it might be quicker to open those older files then copy and paste one way or the other the few things that may have changed between then and now and then save it to a new composite file keeping both of the original files until you are sure you have all the updated work copied over. If your not using session files they are amazing for things like this and well worth the little extra disc space they use.