Can I fix my parents papers if they entered the country illegally, but moved back to mexico more than 10 years now?

If your mother is not barred by any of the other provisions of the Immigration and Nationality Act such as fraud or misrepresentation, crime, or having reentered the US on or after 4/1/97 after having been previously removed or spending one year illegally in the US, you should be able to petition directly for your mother and have her come back since she has already been out of the US for more than 10 years. She will of course have to prove that she has remained outside the country for that long. Due to the limitations of the Lawyers.com Forums, Alan Lee & Arthur Lee, Esqs.’ (the "Firm") participation in responding to questions posted herein does not constitute legal advice, nor legal representation of the person or entity posting a question. No Attorney/Client relationship is or shall be construed to be created hereby. The information provided herein by the Firm is general, and requires that the poster obtain specific legal advice from an attorney. The poster shall not rely upon the information provided herein as legal advice nor as the basis for making any decisions of legal consequence.