Click a product name to obtain its authorization number. After signing in with your Esri Account, click My Organizations > Licensing > Authorizations. If needed, your account’s primary maintenance contact can obtain authorization numbers from My Esri.
If you are a current ArcGIS for Server customer (ArcGIS 10.4.1 and earlier) and you want to upgrade to ArcGIS 10.5, choose ArcGIS Enterprise.