gifovly: 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 CentOS possible default full paths are:

/usr/bin/gifovly - from package: giflib-utils

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

On Debian possible default full paths are:

/usr/bin/gifovly - from package: giflib-tools

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

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