stag-autoschema: 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 Debian possible default full paths are:

/usr/bin/stag-autoschema - from package: libdata-stag-perl

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