“The user then tries navigates to another page. This page then executes a GET request on my REST service which returns a list which is displayed in a table. But while executing the GET request, I receive the error:” Which page is the user navigating to (please include domains) and what is the GET call that is being made? -- Christopher Savory Software Engineer | EdLogics   From: Grant Marrow <grantmarrow(a)gmail.com&gt; Date: Wednesday, November 16, 2016 at 1:26 PM To: Chris Savory <chris.savory(a)edlogics.com&gt; Subject: Re: [keycloak-user] No 'Access-Control-Allow-Origin' header is present on the requested resource Hi Chris Thanks for getting back to me.  I have done that and it didnt work.  I have also tired adding *. That did not work as well. What else can I try? Please let me know. Thanks Regards Grant  On 16 Nov 2016 20:15, "Chris Savory" <chris.savory(a)edlogics.com&gt; wrote: In the admin, click on Clients, then select your client.  Do you have any values for “Web Origins” there?  If not, you need to add ‘http://localhost:9000’ -- Christopher Savory Software Engineer | EdLogics www.edlogics.com <http://www.edlogics.com/>  <http://www.edlogics.com/>  <https://www.linkedin.com/company/edlogics> <https://twitter.com/EdLogics> On 11/16/16, 1:08 PM, &quot;keycloak-user-bounces(a)lists.jboss.org on behalf of Grant Marrow" <keycloak-user-bounces(a)lists.jboss.org on behalf of grantmarrow(a)gmail.com&gt; wrote:     Hi,     I really need some help. I keep on getting the following error:     *No 'Access-Control-Allow-Origin' header is present on the requested     resource. Origin 'http://localhost:9000 <http://localhost:9000/>' is     therefore not allowed access. The response had HTTP status code 500.*     This is my setup:     *Front End:*     - angular 1.5 web application running at http://localhost:9000     - client configuration on keycloak admin console:     - keycloak.json:     {       "realm": "leap",       "auth-server-url": "http://localhost:8080/auth",       "ssl-required": "external",       "resource": "leap-web",       "public-client": true     }     *Auth Server*     - keycloak version 2.30Final running at http://localhost:8080     *Web service*     - java REST service running on Tomcat version 8.5     - client config on keycloak admin console:     - web.xml of rest service:     <web-app xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns="     http://java.sun.com/xml/ns/javaee" xsi:schemaLocation="     http://java.sun.com/xml/ns/javaee     http://java.sun.com/xml/ns/javaee/web-app_3_0.xsd" id="WebApp_ID"     version="3.0">       <display-name>Archetype Created Web Application</display-name>       <module-name>leap-service</module-name>      <listener>         <listener-class>com.hm.leap.service.init.ContextListener</listener-class>       </listener>     <context-param>     <param-name>persistentUnit</param-name>     <param-value>leap</param-value>     </context-param>       <security-constraint>       <web-resource-collection>       <web-resource-name>Leap-Service</web-resource-name>       <url-pattern>/resources/private/*</url-pattern>       </web-resource-collection>       <auth-constraint>       <role-name>user</role-name>       </auth-constraint>       </security-constraint>        <login-config>             <auth-method>KEYCLOAK</auth-method>             <realm-name>leap</realm-name>        </login-config>       <security-role>       <role-name>user</role-name>       </security-role>     </web-app>     - I also have the valve setup on my context.xml that lives in the META-INF     directory     <Context path="/leap-service">     <Valve     className="org.keycloak.adapters.tomcat.KeycloakAuthenticatorValve"/>     </Context>     - keycloak.json:     {       "realm": "leap",       "bearer-only": true,       "auth-server-url": "http://localhost:8080/auth",       "ssl-required": "external",       "resource": "leap-service",       "enable-cors": true     }     The error occurs in the following scenario:     - The angular web app launches, the user clicks the login button which     redirects to Keycloak. The user signs in. The user then tries navigates to     another page. This page then executes a GET request on my REST service     which returns a list which is displayed in a table. But while executing the     GET request, I receive the error:     *No 'Access-Control-Allow-Origin' header is present on the requested     resource. Origin 'http://localhost:9000 <http://localhost:9000/>' is     therefore not allowed access. The response had HTTP status code 500.*     In my Tomcat log file. I see the following warning message:     *11-Nov-2016 11:28:19.464 WARNING [http-nio-8081-exec-2]     org.apache.catalina.authenticator.FormAuthenticator.forwardToLoginPage No     login page was defined for FORM authentication in context [/leap-service]*     I really can't seen to pinpoint the error. I find it quite strange because     I have the same setup but using an older version of keycloak (1.9*), which     worked fine. I know this might be a silly problem, but if you have some     time to help me, I would really appreciate it. Thanks.     Regards     Grant     _______________________________________________     keycloak-user mailing list     keycloak-user(a)lists.jboss.org     https://lists.jboss.org/mailman/listinfo/keycloak-user