cmigrep: 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/cmigrep - from package: cmigrep

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

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