epiunwarp: 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/lib/cmtk/bin/epiunwarp - from package: cmtk

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

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