text2html: 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/text2html - from package: perl-HTML-FromText

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

Error in other languages:
text2html: bevel nie gevind nie
text2html: comandă negăsită
text2html: comando não encontrado
text2html: commande introuvable
text2html: command not found
text2html: käsku ei ole
text2html: không tìm thấy lệnh
text2html: komanda nerasta
text2html: Kommando nicht gefunden.
text2html: kommandot finns inte
text2html: komut yok
text2html: nie znaleziono polecenia
text2html: níor aimsíodh an t-ordú
text2html: no se encontró la orden
text2html: no s'ha trobat l'ordre
text2html: opdracht niet gevonden
text2html: parancs nem található
text2html: perintah tidak ditemukan
text2html: príkaz nenájdený
text2html: příkaz nenalezen
text2html: команда не найдена
text2html: командата не е открита
text2html: 命令找不到
text2html: コマンドが見つかりません