SFTP Connection Closed

Hey when trying to connect to a server using a key I get
sftp -o 'Port=22' -o'IdentityFile=/home/datatel/.ssh/id_dsa_xei' becker_xei@host Connecting to host...
ANGEL SFTP ServerConnection closed by host
Connection closed

Any ideas?

Best add a "-v" to see more details about it and I guess your public key is in the authorized_keys of this server you are trying to connect to?