dzen2-gdbar: 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/dzen2-gdbar - from package: dzen2

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

On Debian possible default full paths are:

/usr/bin/dzen2-gdbar - from package: dzen2

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

Error in other languages:
dzen2-gdbar: bevel nie gevind nie
dzen2-gdbar: comandă negăsită
dzen2-gdbar: comando não encontrado
dzen2-gdbar: commande introuvable
dzen2-gdbar: command not found
dzen2-gdbar: käsku ei ole
dzen2-gdbar: không tìm thấy lệnh
dzen2-gdbar: komanda nerasta
dzen2-gdbar: Kommando nicht gefunden.
dzen2-gdbar: kommandot finns inte
dzen2-gdbar: komut yok
dzen2-gdbar: nie znaleziono polecenia
dzen2-gdbar: níor aimsíodh an t-ordú
dzen2-gdbar: no se encontró la orden
dzen2-gdbar: no s'ha trobat l'ordre
dzen2-gdbar: opdracht niet gevonden
dzen2-gdbar: parancs nem található
dzen2-gdbar: perintah tidak ditemukan
dzen2-gdbar: príkaz nenájdený
dzen2-gdbar: příkaz nenalezen
dzen2-gdbar: команда не найдена
dzen2-gdbar: командата не е открита
dzen2-gdbar: 命令找不到
dzen2-gdbar: コマンドが見つかりません