trash-empty: 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/trash-empty - from package: trash-cli

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

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