GenIssuerAltNameExt: 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/GenIssuerAltNameExt - from package: pki-java-tools

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

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