smbtree: command not found

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 CentOS possible default full paths are:

/usr/bin/smbtree - from package: samba4-client
/usr/bin/smbtree - from package: samba-client

You may install the required package with command yum install {package}

On Debian possible default full paths are:

/usr/bin/smbtree - from package: smbclient

You may install the required package with command apt-get install {package}

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