Chosen Solution

When open a file that is worked for 2 days, the illustrator show an error box: Can’t open the illustration. Could not complete the requested operation. Then the opened file has only a blank layer.

It sounds like it got corrupted then. I doubt you will be able to do anything to recover it… But at least you have the option to try to save the information from the file using Illustrator Recovery Toolbox. http://www.oemailrecovery.com/illustrato… Are you working off of a local hard drive or across a network to a file server? You might have some issues with your network if it is the latter.