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

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

On Debian possible default full paths are:

/usr/bin/rpcclient - from package: smbclient

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

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