Drawing recovery after message saying "drawing file is not valid"

[JamesPowell7164]

I have produced a drawing and zipped it up to send to a client via email. When received my client said that he couldn't open the file as it was corrupt. Upon questioning him he said that the drawing came up as "Drawing file is not valid". I then went to my machine and tried to open it and got the same message.

I am currently using AutoCAD LT 2010 and the drawing was working perfectly until I zipped it up. Does anyone have any ideas on how I can recover the drawing. I have done the usual recover, tried to open the sv$ and ac$ and back up files.

As usual, the system error fairies waited until I hadn't backed up properly before attacking me with this problem.

Any help would be appreciated.

[pendean]

So you zipped another DWG file or file(s) as a test and it is also corrupt?

And your method of ZIP? or App?

ZIP is a reality we do daily and no files are corrupt yet unless it got so during transmission/email (happens).

[JamesPowell7164]

I placed a copy of the drawing into a zip file using WinZIP 14. This copy was corrupt so I went to the original file that I had created and that had been corrupted too. Hence I am having a problem with getting back to the file that is working.

[Anonymous]

It may be too late to suggest this for this instance, but it might be good practice to periodically purge any open drawings, and perhaps to use RECOVER to open drawing files. Okay so OP did you try inserting the problem drawing into a new drawing as a block?

[pendean · Accepted solution]

Sounds like your file was corrupt to start with: Windows since XP (maybe earlier) has had a built-in ZIP tool, for free, worth using. Fid your BAK file, find your Autosave backup file, find yesterday's server backup file and restore. use AUDIT or RECOVER command to open and fix your files.

AutoCAD/LT since, well not sure but for a very very long time now, has had ETRANSMIT command that basically does file packaging (including Zip) and captures all content needed, ready to email to others too. Explore this as a better alternate when sending DWG files.

[JamesPowell7164]

Thanks Modman for suggestions and your help.

I have tried to insert the drawing file into a new drawing but it comes up with a message saying that it was produced by an "incompatible version of AutoCAD LT". This isn't possible as I made the drawing initially, although as explained, there are other objects from external sources in it. It was, however, opening and closing fine until I zipped it up. That isn't to say that the zipping had anything to do with it being corrupted. Logically it can't have as the original as well as the zipped file are corrupted.

I have lost, in effect, 2 very long weeks work on this drawing and it is very frustrating, albeit possibly avoidable.

[JamesPowell7164]

Dean

Reluctantly and ashamedly I think that I have to accept your proven knowledge yet again! Thanks for the suggestion and the help. It is very much appreciated. It is good to know that there is a place to go and ask when all else seems to fail.

[JamesPowell7164]

ETRANSMIT

why oh why have I not used this before?????????

[Anonymous]

"incompatible version" sometimes points to a drawing or an element in a drawing, that was created with a newer version. There's a free converter program available from here that might help, if that's the problem...

[pendean]

The OP is using LT2010 (newer is not there for the DWG format), so -EXPORTTOAUTOCAD command should fix the file by exploding many such objects to their basics: might not be desireable in a few situation but fine for most.