Passu 1: Apri cmd (eseguite cum'è amministratore), then you type
dism /online /get-targeteditions
Passu 2: You copy and paste this code in cmd
If you want to upgrade to Windows Server 2012 R2 Standard chì scrivite:
dism /online /set-edition:serverstandard /productkey:XXXXX-XXXXX-XXXXX-XXXXX-XXXXX /accepteula
Nota:
se vede "l'aghjurnamentu falliu", riavviate u vostru servitore Windows 2012 R2. It will upgrade Windows Server 2012 R2 Evaluation to Standard.