taskadmin: 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/taskadmin - from package: python2-boto
/usr/bin/taskadmin - from package: python-boto

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

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