w3mman: 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/w3mman - from package: w3m

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

On Debian possible default full paths are:

/usr/bin/w3mman - from package: w3m

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

Error in other languages:
w3mman: bevel nie gevind nie
w3mman: comandă negăsită
w3mman: comando não encontrado
w3mman: commande introuvable
w3mman: command not found
w3mman: käsku ei ole
w3mman: không tìm thấy lệnh
w3mman: komanda nerasta
w3mman: Kommando nicht gefunden.
w3mman: kommandot finns inte
w3mman: komut yok
w3mman: nie znaleziono polecenia
w3mman: níor aimsíodh an t-ordú
w3mman: no se encontró la orden
w3mman: no s'ha trobat l'ordre
w3mman: opdracht niet gevonden
w3mman: parancs nem található
w3mman: perintah tidak ditemukan
w3mman: príkaz nenájdený
w3mman: příkaz nenalezen
w3mman: команда не найдена
w3mman: командата не е открита
w3mman: 命令找不到
w3mman: コマンドが見つかりません