Drawing contains Xrefs which are either unloaded or unresolved and do not show up in the base drawing.
I am unable to reload but can detach some of them.
When I try to Xref a new file it does not function. Makes no differerence whether its an attachment or an overlay.
Do you know if the drawings came from a program different from ACAD? I have had the unfortunate experience of circular references from Microstation in ACAD and the only way I was able to fix the xref issues was to use the "Reference Manager". The program is under Start->All Programs->Autodesk->Civil 3d 20XX->Reference Manager.
I would recommend you move all DWG files to a single folder. When you add the files, it will prompt for what to do with x-refs, start off by "Add only the fist-level xrefs". Then you should be able to fix the errors.
Another possibility: what acad version was used to save the xref files -- or more importantly, what format are they saved in? If they were saved in 2014 and you're trying to open a dwg using 2012, then 2012 will not be able to read the 2014 files and therefore will not display them. Although I would have expected to see a message that the file(s) couldn't be read to the file version.
You said that the files are either UNLOADED or UNRESOLVED. Have you checked to be sure acad is actually able to find them? Meaning are they in the same folder as your current drawing? In a folder included in the search path? Is the full path specified and does that path exist at your location?
ALL the CAD files are in a SINGLE folder.
The drawings were created in version 2005 and I am now using 2013.
There may also be a PROJECT FOLDER that was once connected with the directory for the DWG's.
Trying to XREF is basically non-functional.
This could be a file corruption problem as well. If you save the files to DXF and reopen them, it may dump the corrupted data. I've had to do that with jacked up embedded aecc objects that came from architect or survey files.
I can think of a few of factors causing the behavior.
Usually when a reference won't detach it's because it is nested in another Xref which is attached. By toggling the XREF manager to tree mode you can easily identify which XREF's are nested. You'll have to detach the host XREF's to get rid of them. Now if an attached host XREF has nested xref's and it's files can't be found, you'll have to correct the problem in the host XREF.
Another problem can occur when an xref is bound into the drawing as a block and then that block is erased. While the block does not appear in the drawing it is still in the block database. Thus if you attempt to re-attach the original XREF it fails because the name conflicts with the block. You have to first purge the block (or rename it if you want to keep it). A good clue to tell if this is the problem is to watch the command line when you attempt to attach the file. It will tell you there is a conflict.
If you attempt to attach a file that is in an unsupported format you may not see any warning dialogue about the incompatible file, just a little comment on the command line.
Sometimes an attached XREF accidently gets selected and deleted in the drawing. The handle remains attached but there are no graphics anymore. In this case you have to delete the handles and re-attach the file. Use QSELECT to select the handles and then erase them.
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