linux-helper: 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/lib/R/site-library/BatchJobs/bin/linux-helper - from package: r-cran-batchjobs

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

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