faxsend: 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/faxsend - from package: hylafax+

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

On Debian possible default full paths are:

/usr/sbin/faxsend - from package: capi4hylafax
/usr/sbin/faxsend - from package: hylafax-server

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

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