lastex: 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/lastex - from package: last-align

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

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