A Forum ban, also known as a Forum mute is a punishment issued by Jagex to players who misuse the RuneScape forums. They are typically issued against players who post spam threads, flame or troll other users, or otherwise deliberately misuse the offical forums.
Initially, Jagex made a '3 strike rule' for issuing this type of punishment. Players that intentionally misused the forums once were issued a warning. A temporary forum ban was issued to players for the second offence, along with a final warning. Players who committed a third offence on the forums were issued a permanent forum ban.
As of 11 May 2009, forum bans were removed, and became concurrent with mutes. More specifically, mutes and forum bans became the same punishment. Players who are muted in-game cannot post on the forums. Likewise, players who have their forum posting priveleges removed will be muted in-game.
However, a recent hidden update once again made forum bans no longer affect one's ability to speak in-game. Nevertheless, for more severe forum offences, an in-game mute can still be applied, and a player who is already muted in-game will be banned from the forums for the duration of the mute.