A petition to allow gamers to run their own servers for the original World of Warcraft (WoW) game has attracted more than 100,000 signatures online.
Games studio Blizzard Entertainment no longer operates servers for the original WoW, which was first released in 2004, so some fans run their own.
On 10 April, a popular fan server known as Nostalrius, with 150,000 active members, was closed after the threat of legal action by Blizzard Entertainment.
Blizzard has not responded to the BBC.
World of Warcraft is an online multi-player game in which players explore a vast landscape, complete quests and interact with other gamers.
The original game from 2004 has since been updated with new instalments that some players say have materially changed the experience of the game, so some fans have set up their own servers to play the original, "vanilla" WoW.
Blizzard has previously said it had no plans to reopen access to the "classic" game.
"We realise that some of you feel that World of Warcraft was more fun in the past than it is today, and we also know that some of you would like nothing more than to go back and play the game as it was back then," wrote a Blizzard community manager in 2011.
"The developers however prefer to see the game continuously evolve and progress, and as such we have no plans to open classic realms or limited expansion content realms."
The decision to close fan-run server Nostalrius, which had attracted 800,000 players during its year online, has prompted anger from parts of the online gaming community.
Many who commented on the closure acknowledged the fact that running servers such as Nostalrius was technically illegal but said Blizzard should support non-profit fan-driven projects to keep the game going.
"World of Warcraft meant a lot, to a lot of people," said YouTube gamer Jon Jafari in a widely-shared video.
"It might seem silly because it's just a game... but this game was a big part of my life and a lot of people's lives. All these people want to do is go back and play it.
"If the server is making a profit, I can see them taking down something like that - but a lot of these are just for the love of the old game."
Commenting on its closure, the team behind Nostalrius posted: "We never saw our community as a threat for Blizzard. It sounds more like a transverse place where players can continue to enjoy old World of Warcraft's games no longer available."