ipe6upgrade: 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/ipe6upgrade - from package: ipe

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

Error in other languages:
ipe6upgrade: bevel nie gevind nie
ipe6upgrade: comandă negăsită
ipe6upgrade: comando não encontrado
ipe6upgrade: commande introuvable
ipe6upgrade: command not found
ipe6upgrade: käsku ei ole
ipe6upgrade: không tìm thấy lệnh
ipe6upgrade: komanda nerasta
ipe6upgrade: Kommando nicht gefunden.
ipe6upgrade: kommandot finns inte
ipe6upgrade: komut yok
ipe6upgrade: nie znaleziono polecenia
ipe6upgrade: níor aimsíodh an t-ordú
ipe6upgrade: no se encontró la orden
ipe6upgrade: no s'ha trobat l'ordre
ipe6upgrade: opdracht niet gevonden
ipe6upgrade: parancs nem található
ipe6upgrade: perintah tidak ditemukan
ipe6upgrade: príkaz nenájdený
ipe6upgrade: příkaz nenalezen
ipe6upgrade: команда не найдена
ipe6upgrade: командата не е открита
ipe6upgrade: 命令找不到
ipe6upgrade: コマンドが見つかりません