userv: 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/bin/userv - from package: userv

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

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