dh_installgsettings: 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/dh_installgsettings - from package: debhelper

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

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