gophfilt: 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 Debian possible default full paths are:

/usr/bin/gophfilt - from package: gopher

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