acpid: 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/sbin/acpid - from package: acpid

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

On Debian possible default full paths are:

/usr/sbin/acpid - from package: acpid

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

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