glade-previewer: 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/glade-previewer - from package: glade

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

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