kolourpaint: 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/kolourpaint - from package: kdegraphics

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

On Debian possible default full paths are:

/usr/bin/kolourpaint - from package: kolourpaint4

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

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