glib-compile-schemas: command not found

Have You tried accessing the binary with the full path?

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/glib-compile-schemas - from package: glib2

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

On Debian possible default full paths are:

/usr/bin/glib-compile-schemas - from package: libglib2.0-bin

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