In some environments, adding an unsecured server service to a Portal for ArcGIS 10.3.1 web map, secured with Windows users from a GIS server tier token-based security site with '/MapServer/#', prompts for user credentials. By clicking ‘Cancel’ or ‘Close’ on the authentication box, the queries are returned. However, this causes other issues in the portal site where invalid tokens are appended to the requests for services embedded in the web map.