sisu-html-seg: 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/sisu-html-seg - from package: sisu

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

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