grep-changelog.emacs24: 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/grep-changelog.emacs24 - from package: emacs24-bin-common

You may install the required package with command apt-get install {package}
Error in other languages:
grep-changelog.emacs24: bevel nie gevind nie
grep-changelog.emacs24: comandă negăsită
grep-changelog.emacs24: comando não encontrado
grep-changelog.emacs24: commande introuvable
grep-changelog.emacs24: command not found
grep-changelog.emacs24: käsku ei ole
grep-changelog.emacs24: không tìm thấy lệnh
grep-changelog.emacs24: komanda nerasta
grep-changelog.emacs24: Kommando nicht gefunden.
grep-changelog.emacs24: kommandot finns inte
grep-changelog.emacs24: komut yok
grep-changelog.emacs24: nie znaleziono polecenia
grep-changelog.emacs24: níor aimsíodh an t-ordú
grep-changelog.emacs24: no se encontró la orden
grep-changelog.emacs24: no s'ha trobat l'ordre
grep-changelog.emacs24: opdracht niet gevonden
grep-changelog.emacs24: parancs nem található
grep-changelog.emacs24: perintah tidak ditemukan
grep-changelog.emacs24: príkaz nenájdený
grep-changelog.emacs24: příkaz nenalezen
grep-changelog.emacs24: команда не найдена
grep-changelog.emacs24: командата не е открита
grep-changelog.emacs24: 命令找不到
grep-changelog.emacs24: コマンドが見つかりません