It is thought that thousands of Britons flooded the site, which was due to begin selling its allocation to pre-registered applicants at 8am today.
It is believed the reselling agent’s website, Eventeam2012.fr, crashed without selling a single ticket.
Those trying to access the site were greeted with the message: "For technical reasons we invite you to return to the site www.eventeam2012.fr from 14.00. Thank you for your understanding."
The website was still not up-and-running when this story was published.
It is thought the overloading of the French system came about because of a rush for tickets by people from across Europe, including thousands of UK residents, who had pre-registered for the chance to purchase tickets, a system that was designed to give users a 48-hour window of private sales before the site was opened to the general public.
The Olympic ticketing process has come under fire from UK residents who had to enter ballots for tickets and then had money taken from accounts prior to knowing which tickets they had been successful in purchasing.
Details of a second round of ticket sale, which will give priority to those who did not get a ticket in the original ballot, are expected to be announced by Locog this week.