genrestr: 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/genrestr - from package: gromacs

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

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