--worker_name has been renamed to --worker-name
Noticed that. But same error.
In the batfile tbminer_unmineable_eth, it has the correct launch parameter to connect to this pool.
TBMiner --algo ethash --hostname ethash.unmineable.com --port 3333 --wallet ETH:%ETH_WALLET% --worker-name %computername%
Outch. Didnt noticed, sorry 4 my stupidity.