The preview is not an indication of content, but only what was there when
the file was last successfully saved.
Try ZOOM>Extents, or window the middle of your screen and see if any blue
blips show up, then Zoom>Window down to it to confirm that's your 'content'.
Also start XREF command and see if you simply 'misplaced' the xref files
that are supposed to be in there.
Also toggle between model and layouts, see if anything shows up.
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Dean Saadallah
Add-on products for LT
http://www.pendean.com/lt
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