lessfile: 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:

/bin/lessfile - from package: less
/usr/bin/lessfile - from package: less

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

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