akonadi_mailtransport_dummy_resource: 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/akonadi_mailtransport_dummy_resource - from package: kdepim-runtime

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

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