nexcontrol: 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/nexcontrol - from package: nexcontrol

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

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