ctmconv: 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/ctmconv - from package: openctm-tools

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