ldapmodifyuser: 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 Debian possible default full paths are:

/usr/sbin/ldapmodifyuser - from package: ldapscripts

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

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