kwriteconfig: 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/kwriteconfig - from package: kdebase-runtime

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

On Debian possible default full paths are:

/usr/bin/kwriteconfig - from package: kde-runtime

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

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