podtree2html: command not found

Have You tried accessing the binary with the full path?

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/podtree2html - from package: libpod-tree-perl

You may install the required package with command apt-get install {package}
Error in other languages:
podtree2html: bevel nie gevind nie
podtree2html: comandă negăsită
podtree2html: comando não encontrado
podtree2html: commande introuvable
podtree2html: command not found
podtree2html: käsku ei ole
podtree2html: không tìm thấy lệnh
podtree2html: komanda nerasta
podtree2html: Kommando nicht gefunden.
podtree2html: kommandot finns inte
podtree2html: komut yok
podtree2html: nie znaleziono polecenia
podtree2html: níor aimsíodh an t-ordú
podtree2html: no se encontró la orden
podtree2html: no s'ha trobat l'ordre
podtree2html: opdracht niet gevonden
podtree2html: parancs nem található
podtree2html: perintah tidak ditemukan
podtree2html: príkaz nenájdený
podtree2html: příkaz nenalezen
podtree2html: команда не найдена
podtree2html: командата не е открита
podtree2html: 命令找不到
podtree2html: コマンドが見つかりません