cpp2html: 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/cpp2html - from package: source-highlight

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

Error in other languages:
cpp2html: bevel nie gevind nie
cpp2html: comandă negăsită
cpp2html: comando não encontrado
cpp2html: commande introuvable
cpp2html: command not found
cpp2html: käsku ei ole
cpp2html: không tìm thấy lệnh
cpp2html: komanda nerasta
cpp2html: Kommando nicht gefunden.
cpp2html: kommandot finns inte
cpp2html: komut yok
cpp2html: nie znaleziono polecenia
cpp2html: níor aimsíodh an t-ordú
cpp2html: no se encontró la orden
cpp2html: no s'ha trobat l'ordre
cpp2html: opdracht niet gevonden
cpp2html: parancs nem található
cpp2html: perintah tidak ditemukan
cpp2html: príkaz nenájdený
cpp2html: příkaz nenalezen
cpp2html: команда не найдена
cpp2html: командата не е открита
cpp2html: 命令找不到
cpp2html: コマンドが見つかりません