I once misspelled earthcoin.conf (earthcoin.config).
There is somewhere a mistake you are overlooking, probably a spelling mistake.
Maybe a mistake with your earthcoin.conf?
Check rpcallowip=192.168.1.*
rpcconnect=192.168.1.*
Adjust these IP ranges to your router IP.
Maybe a mistake with your username/password you defined in earthcoin.conf.
Also, if the wallet (server) is on the same computer as the miner, use localhost:15678 - if it's on a different computer, use local IP of wallet computer on your mining computer.
e.g. http://192.168.1.126:15678
I tried your .bat, checked pass and pw and checked router-ip, my ip trough dhcp... everything fits. this is strange!