ssh-contact: command not found

Have You tried accessing the binary with the full path?

Maybe Your $PATH variable doesn't contain the default paths? echo $PATH should give something like:

[root@server ~]# echo $PATH
/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin:/root/bin

If it's empty, You may set the PATH variable with this command

export PATH="/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin:/root/bin"

On Debian possible default full paths are:

/usr/bin/ssh-contact - from package: ssh-contact-client

You may install the required package with command apt-get install {package}
Error in other languages:
ssh-contact: bevel nie gevind nie
ssh-contact: comandă negăsită
ssh-contact: comando não encontrado
ssh-contact: commande introuvable
ssh-contact: command not found
ssh-contact: käsku ei ole
ssh-contact: không tìm thấy lệnh
ssh-contact: komanda nerasta
ssh-contact: Kommando nicht gefunden.
ssh-contact: kommandot finns inte
ssh-contact: komut yok
ssh-contact: nie znaleziono polecenia
ssh-contact: níor aimsíodh an t-ordú
ssh-contact: no se encontró la orden
ssh-contact: no s'ha trobat l'ordre
ssh-contact: opdracht niet gevonden
ssh-contact: parancs nem található
ssh-contact: perintah tidak ditemukan
ssh-contact: príkaz nenájdený
ssh-contact: příkaz nenalezen
ssh-contact: команда не найдена
ssh-contact: командата не е открита
ssh-contact: 命令找不到
ssh-contact: コマンドが見つかりません