gpgsm-gencert.sh: 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/gpgsm-gencert.sh - from package: gnupg2-smime

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

On Debian possible default full paths are:

/usr/bin/gpgsm-gencert.sh - from package: gpgsm

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

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