md2html.js: 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/lib/node_modules/markdown/bin/md2html.js - from package: nodejs-markdown

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

Error in other languages:
md2html.js: bevel nie gevind nie
md2html.js: comandă negăsită
md2html.js: comando não encontrado
md2html.js: commande introuvable
md2html.js: command not found
md2html.js: käsku ei ole
md2html.js: không tìm thấy lệnh
md2html.js: komanda nerasta
md2html.js: Kommando nicht gefunden.
md2html.js: kommandot finns inte
md2html.js: komut yok
md2html.js: nie znaleziono polecenia
md2html.js: níor aimsíodh an t-ordú
md2html.js: no se encontró la orden
md2html.js: no s'ha trobat l'ordre
md2html.js: opdracht niet gevonden
md2html.js: parancs nem található
md2html.js: perintah tidak ditemukan
md2html.js: príkaz nenájdený
md2html.js: příkaz nenalezen
md2html.js: команда не найдена
md2html.js: командата не е открита
md2html.js: 命令找不到
md2html.js: コマンドが見つかりません