Unsure if it's new or not, but it's on their website: http://us.battle.net/support/en/article/diablo-iii-installation-troubleshooting-mac http://us.battle.net/s

Unsure if it's new or not, but it's on their website: http://us.battle.net/support/en/article/diablo-iii-installation-troubleshooting-mac http://us.battle.net/support/en/article/diablo-iii-installat... "This error is caused when FileVault options are enabled, or if a volume is formatted as case-sensitive. These options are not supported for installation." "If FileVault is enabled, then Diablo III will not install."