Problem: The option to store credentials when adding secured services is not visible in Portal for ArcGIS
Credentials for services used in Portal for ArcGIS can be stored to enable future usage without having to log in every time the map is opened. However, there are certain cases where the option to store credentials is not visible, hence the credentials for the services cannot be stored.
There are several possible causes for this problem:
The services are secured with web-tier authentication, for example, Integrated Windows Authentication (IWA). This behavior is by default.
The services are inaccessible by Portal for ArcGIS. This may occur if the service is blocked by a firewall, or the services proxy is not configured correctly.
The SSL certificate used by the service is not trusted by Portal for ArcGIS.
Solution or Workaround
Use one of the following solutions, depending on the cause: