hivexsh: 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 CentOS possible default full paths are:

/usr/bin/hivexsh - from package: hivex

You may install the required package with command yum install {package}

On Debian possible default full paths are:

/usr/bin/hivexsh - from package: libhivex-bin

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

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