rpcclient.h: 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 Debian possible default full paths are:

/usr/include/cxxtools/bin/rpcclient.h - from package: libcxxtools-dev

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

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