assistant_adp: 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/assistant_adp - from package: qt-x11
/usr/lib64/qt4/bin/assistant_adp - from package: qt-x11
/usr/lib/qt4/bin/assistant_adp - from package: qt-x11

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

On Debian possible default full paths are:

/usr/bin/assistant_adp - from package: qt-assistant-compat
/usr/lib/x86_64-linux-gnu/qt4/bin/assistant_adp - from package: qt-assistant-compat

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

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