3144833 - Portal shows blank screen when launching Fiori Framework Page

• The Fiori Framework Page is blank when accessed
• Checking the browser Network trace, an error 500 is returned for:
  <protocol>://<host>:<port>/AFPServlet/NavigationServlet?action=getSubTree&numberOfLevels=10[...]
• The Default Trace contains an error:
  javax.ejb.EJBException: ASJ.ejb.005043 (Failed in component: sap.com/com.sap.portal.navigation.ws.NavigationWSEar, EP-PIN-NAV) Exception raised from invocation of public com.sap.portal.navigation.ws.NavigationTreeResponse com.sap.portal.navigation.ws.NavigationWSBean.getNavigationTree(com.sap.portal.navigation.ws.NavigationTreeRequest) method on bean instance com.sap.portal.navigation.ws.NavigationWSBean@4291c73b for bean sap.com/com.sap.portal.navigation.ws.NavigationWSEar*xml|com.sap.portal.navigation.ws.NavigationWSBean.jar*xml|NavigationWS in application sap.com/com.sap.portal.navigation.ws.NavigationWSEar.; nested exception is: java.lang.StringIndexOutOfBoundsException: String index out of range: -1
  java.lang.StringIndexOutOfBoundsException: String index out of range: -1
  at java.lang.String.substring(String.java:2013)
  at com.sapportals.portal.navigation.NavigationService.getExternalConnectorPrefix(NavigationService.java:2845)
  at com.sapportals.portal.navigation.NavigationService.getExternalNodeChildrenNA(NavigationService.java:2815)
  at com.sapportals.portal.navigation.NavigationNode.getChildrenBeforeMerge(NavigationNode.java:506)
  ...

• SAP NetWeaver Application Server for Java 7.50
• FLP@EP

ffp, flp, flp@ep, enterprise, portal, fiori, launchpad, blank, empty, exception, missing, tiles, error, 500, external, connector , KBA , EP-PIN-NAV-FFP , Fiori Framework Page , EP-PIN-NAV , Navigation , Problem