Hi,
first at all: copy your BAK file to another folder, rename it there to .DWG ... it could be your working last version.
Then try command _RECOVER (or in case XRefs are used then start command _RECOVERALL).
If that does not help then please upload the drawing and please let us know which version of AutoCAD you get displayed in the dialog of command _ABOUT (because 20.0 could be an internal version number of AutoCAD 2015, but it's unusual to use that number when speaking about an AutoCAD version).
If all fails you need to restore the files from your backup.
- alfred -
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Alfred NESWADBA
ISH-Solutions GmbH / Ingenieur Studio HOLLAUS
www.ish-solutions.at ...
blog.ish-solutions.at ...
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CDay 2026------------------------------------------------------------------------------------
(not an Autodesk consultant)