w3m: command not found

Have You tried accessing the binary with the full path?

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/w3m - from package: w3m

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

On Debian possible default full paths are:

/usr/bin/w3m - from package: w3m

You may install the required package with command apt-get install {package}
Error in other languages:
w3m: bevel nie gevind nie
w3m: comandă negăsită
w3m: comando não encontrado
w3m: commande introuvable
w3m: command not found
w3m: käsku ei ole
w3m: không tìm thấy lệnh
w3m: komanda nerasta
w3m: Kommando nicht gefunden.
w3m: kommandot finns inte
w3m: komut yok
w3m: nie znaleziono polecenia
w3m: níor aimsíodh an t-ordú
w3m: no se encontró la orden
w3m: no s'ha trobat l'ordre
w3m: opdracht niet gevonden
w3m: parancs nem található
w3m: perintah tidak ditemukan
w3m: príkaz nenájdený
w3m: příkaz nenalezen
w3m: команда не найдена
w3m: командата не е открита
w3m: 命令找不到
w3m: コマンドが見つかりません