go2summary: 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 Debian possible default full paths are:

/usr/bin/go2summary - from package: libgo-perl

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

Error in other languages:
go2summary: bevel nie gevind nie
go2summary: comandă negăsită
go2summary: comando não encontrado
go2summary: commande introuvable
go2summary: command not found
go2summary: käsku ei ole
go2summary: không tìm thấy lệnh
go2summary: komanda nerasta
go2summary: Kommando nicht gefunden.
go2summary: kommandot finns inte
go2summary: komut yok
go2summary: nie znaleziono polecenia
go2summary: níor aimsíodh an t-ordú
go2summary: no se encontró la orden
go2summary: no s'ha trobat l'ordre
go2summary: opdracht niet gevonden
go2summary: parancs nem található
go2summary: perintah tidak ditemukan
go2summary: príkaz nenájdený
go2summary: příkaz nenalezen
go2summary: команда не найдена
go2summary: командата не е открита
go2summary: 命令找不到
go2summary: コマンドが見つかりません