tor-gencert: 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 CentOS possible default full paths are:

/usr/bin/tor-gencert - from package: tor

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

On Debian possible default full paths are:

/usr/bin/tor-gencert - from package: tor

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

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