The United States is reviewing its green card lottery after the results of this year's draw were scratched, leaving 22,000 told in error that they had been chosen for a chance at US residency.
The State Department said a computer failed to run a valid random selection for the lottery.
More than 19 million people entered the lottery, which is intended to diversify the pool of new US arrivals.
The results of a new drawing of names will be posted in July.
The lottery, began in 1994 as a way to encourage immigration from countries under-represented among new arrivals to the United States.
The programme offers 50,000 visas every year and recipients are granted permanent resident status and may apply for US citizenship.
To be eligible, applicants must have a high school education or the equivalent and have two years of experience in a profession.
The visas are awarded in what is supposed to be a random selection run by a computer.
But the BBC reports a computer glitch selected more than 90% of those names from people who applied within the first two days of the registration period.
The invalid results were posted to the programme's website in May.
''They were posted in error,'' deputy assistant secretary of state David Donahue said last month. ''These results are not valid because they did not represent a fair, random selection of entrants as required by US law.''