Users were unable to access a number of UK sites, including the Radio Times, when they were wrongly blocked for copyright infringement.
According to the BBC, internet service providers (ISPs) were ordered by the High Court to block the internet protocol (IP) addresses of First Row Sports, which streams football games.
But the site shared an IP address with other websites, including the Radio Times. This meant when users typed in "radiotimes.com" rather than "www.radiotimes.com" they were prevented from reaching the site.
The court stated that it has no obligation to check the validity of which IP addresses should be blocked and that ISPs must rely on claims to be accurate.
As well as the Radio Times, football clubs including Blackburn Rovers and other sites were blocked.
"As a responsible ISP, we obey court orders when addressed to the company," said a Virgin Media spokesman. "However, we do not believe the instruction to block this particular IP address meets the criteria of the court order against First Row Sports so we have stopped blocking it and are writing to the Premier League."
BT and Telefonica, which runs Sky’s internet offering, also said they had unblocked the IP address. TalkTalk was not aware of the problem.
The High Court has ordered internet providers to block several sites which have infringed copyright laws, including the Swedish-based file-sharing site The Pirate Bay. While the site experienced an 11% drop in file-sharing initially, its peer-to-peer activity on the network returned to just below normal only a week after the measures were enforced.