The Pentagon has defended its internet voting system after a critical report recommended it should be scrapped.
Four computer experts who reviewed the pilot project said the risks of online voting could not be eliminated.
"It has numerous other fundamental security problems that leave it vulnerable to a variety of well-known cyber attacks," said the report.
The Pentagon is standing by the system, which could be used in November"s presidential elections. The project is part of the Pentagon"s Federal Voting Assistance Program, which was set up in 1986 to help military personnel stationed abroad to to vote.