If person works in the USA without working permit and violates the law. Or if he obtains wrongfully work permit. How long he must not visit the USA? Can he ever ask for at least visitors visa again.

Depends on how it happened.. was he deported? OR was he on voluntary leave? What country is he from? Need more info...

He was not deported. Just when he asked again for visa they have told him that in the system there is an information that he has been illegally working in some places and his last work permit was issued by fraud. Probably someone said them some information. He is from Czech Republic.

He left the country when his visa expired. Just the emigration got this info on him but he never got caught.

He left the country when his visa expired. Just the emigration got this info on him but he never got caught.

Working without authorization is one thing but using faked document plus working illegally really come back and bite him. This is considered immigration fraud and he will be banned from entering US for life.

I have heard that after 7 years all info about the person is deleted from the computer and you start with a clean credit. It is not right?