imapproxyd: 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/sbin/imapproxyd - from package: imapproxy

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

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