pyrcc4: 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/pyrcc4 - from package: PyQt4-devel

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

On Debian possible default full paths are:

/usr/bin/pyrcc4 - from package: pyqt4-dev-tools

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

Error in other languages:
pyrcc4: bevel nie gevind nie
pyrcc4: comandă negăsită
pyrcc4: comando não encontrado
pyrcc4: commande introuvable
pyrcc4: command not found
pyrcc4: käsku ei ole
pyrcc4: không tìm thấy lệnh
pyrcc4: komanda nerasta
pyrcc4: Kommando nicht gefunden.
pyrcc4: kommandot finns inte
pyrcc4: komut yok
pyrcc4: nie znaleziono polecenia
pyrcc4: níor aimsíodh an t-ordú
pyrcc4: no se encontró la orden
pyrcc4: no s'ha trobat l'ordre
pyrcc4: opdracht niet gevonden
pyrcc4: parancs nem található
pyrcc4: perintah tidak ditemukan
pyrcc4: príkaz nenájdený
pyrcc4: příkaz nenalezen
pyrcc4: команда не найдена
pyrcc4: командата не е открита
pyrcc4: 命令找不到
pyrcc4: コマンドが見つかりません