latexmlpost: 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 Debian possible default full paths are:

/usr/bin/latexmlpost - from package: latexml

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

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