imapcopy: 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/imapcopy - from package: imapcopy

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

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