xx-encrypted: 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/xx-encrypted - from package: xxdiff-scripts

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