This file is damaged and could not be repaired

za'inj,

One thing often tried first is to create a new document and File>Place the (PDF contents, if any, of the) corrupted one to see how much may be rescued that way.

Here are some websites where you can see whether it can rescue the actual file, and if it can, you may pay for a subscription to have it done,

http://www.recoverytoolbox.com/buy_illustrator.html

http://markzware.com/adobe-software/fix-illustrator-file-unknown-error-occurred-pdf2dtp-file-recovery/

http://www.illustrator.fixtoolbox.com/

http://www.erepairillustrator.com/

As far as I remember, the first one is for Win and the second one is for Mac, while the third and fourth one should be for both.

Here are a few pages about struggling with it yourself:

http://daxxter.wordpress.com/2009/04/16/how-to-recover-a-corrupted-illustrator-ai-file/

http://helpx.adobe.com/illustrator/kb/troubleshoot-damaged-illustrator-files.html

http://kb2.adobe.com/cps/500/cpsid_50032.html

http://kb2.adobe.com/cps/500/cpsid_50031.html

http://helpx.adobe.com/illustrator/kb/enable-content-recovery-mode-illustrator.html

It is always recommended to create backups with different names regularly, and to store backups in more than one place/way.

And also to save often.

Where did you save the file?

Is this the first time this happened?

What's in the file?

Do you have a printer connected, set up and turned on?

Hi,

Can you confirm your Operating System and add a screenshot of the error message?

Can you test the file on a different computer?