dpns-modifygrpmap: command not found

Have You tried accessing the binary with the full path?

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/dpns-modifygrpmap - from package: dpm

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

On Debian possible default full paths are:

/usr/bin/dpns-modifygrpmap - from package: dpm
/usr/lib/debug/usr/bin/dpns-modifygrpmap - from package: lcgdm-dbg

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