Rsync - ERROR: rsync error: protocol incompatibility (code 2) at compat.c(171) [sender=3.0.6]

$rsync -av file.zip user@host:file.zip
protocol version mismatch -- is your shell clean?
(see the rsync man page for an explanation)
rsync error: protocol incompatibility (code 2) at compat.c(171) [sender=3.0.6]

This message can be somewhat misleading at first glance, but the key to solve this issue is answering what actually means "clean shell" ;). Most probably there is some MOTD (message of the day) displayed in one of the config files (eg. .bashrc) when user starts a new session. To check if it is the case, try the following command:

ssh designer@10.1.1.162 true | wc -c

If this command returns more then 0 that means there is some output produced. Get rid of it should fix it.