dcopstart: 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/dcopstart - from package: kdelibs3

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

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