gdcmpgif: 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/gdcmpgif - from package: gd-progs

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

On Debian possible default full paths are:

/usr/bin/gdcmpgif - from package: libgd-tools

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

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