I am trying to add an Esri basemap to our ArcGIS Enterprise and am not able to store credentials. There is no checkbox for storing credentials. I'm following the directions here https://doc.arcgis.com/en/collector/ios/create-maps/offline-map-prep.htm#ESRI_SECTION1_5ED9DA9CD8D14... to take an Esri basemap offline. ArcGIS Enterprise 10.5.1.
Thanks.
After configuring portal so use a forward proxy server and configuring portal to trust certificates from our CA, we can now save credentials.