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Ok I have download my server world in creative but when I try to switch the game mode
it says [Debug]: Unable to open game mode switcher; no permission
and also for the command it doesn't do anything
PLEASE HELP MEEEEE
is there any world download broken 
please answer me
Open the world to LAN and make sure that cheats are enabled.
Yes. That's because the world itself does not have cheats enabled.
Sharing it to lan overwrites this setting
https://gaming.stackexchange.c…-to-turn-cheats-on-or-off
I don't recommend manually modifying the level.dat file though.
