RCON connection in loacalhost failed

i can't set RCON ip in localhost... i'm fixing a server on my PC but i can't run GSM right
[27.12.16 17:32:14] Info: RCON command executed: 'version'
[27.12.16 17:32:14] Error: RCON connection not valid, check whether your config (IP + port) is correct and your gameserver is running

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Fatal Error killed us

yes, i tried to change 3 times in GSM config and server config too