krandrtray: 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/krandrtray - from package: kdebase-workspace

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

On Debian possible default full paths are:

/usr/bin/krandrtray - from package: kde-workspace-randr

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

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