sl2h: 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/sl2h - from package: noweb

You may install the required package with command apt-get install {package}
Error in other languages:
sl2h: bevel nie gevind nie
sl2h: comandă negăsită
sl2h: comando não encontrado
sl2h: commande introuvable
sl2h: command not found
sl2h: käsku ei ole
sl2h: không tìm thấy lệnh
sl2h: komanda nerasta
sl2h: Kommando nicht gefunden.
sl2h: kommandot finns inte
sl2h: komut yok
sl2h: nie znaleziono polecenia
sl2h: níor aimsíodh an t-ordú
sl2h: no se encontró la orden
sl2h: no s'ha trobat l'ordre
sl2h: opdracht niet gevonden
sl2h: parancs nem található
sl2h: perintah tidak ditemukan
sl2h: príkaz nenájdený
sl2h: příkaz nenalezen
sl2h: команда не найдена
sl2h: командата не е открита
sl2h: 命令找不到
sl2h: コマンドが見つかりません