aewm++_xsession: command not found

Have You tried accessing the binary with the full path?

Maybe Your $PATH variable doesn't contain the default paths? echo $PATH should give something like:

[root@server ~]# echo $PATH

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/aewm++_xsession - from package: aewm++-goodies

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