hexedit: 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/hexedit - from package: hexedit

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

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