Unknown format

[cooeel76]

After upgrading Windows 8.1 to Windows 10 i cannot open one very important AutoCAD (dwg format) file. Getting 'Unknown format' error. I could open it before!

Any thoughts please?
Thanks

 

[Reef Bass]

Windows 10 installation includes removal of programs that are known to not be compatible. Maybe your DWG file opening application fell victim to that?

 

[g.quezada]

In AutoCAD there is a tick box in the purge dialogue to purge orphaned data, make sure this is ticked on.
Take a look at this link to see if it may be related: http://www.dwg.repair/

 

[IPT]

no specific experience with that but have had issues in the past with PS files when the suffix was messed up (though as you said I did nothing to change it). I manually reformatted the suffix and issue was solved. Hope it is something simple like that for you.