xvt: 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/xvt - from package: xvt

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

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