xsp: 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/xsp - from package: mono-xsp

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

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