wxHexEditor: 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/wxHexEditor - from package: wxhexeditor

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

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