pmconfirm: 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/pmconfirm - from package: pcp-gui

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

On Debian possible default full paths are:

/usr/bin/pmconfirm - from package: pcp-gui

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

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