To use gui web administration, you must add a gui role .
In [Tomcat installation path]/conf/tomcat-users.xml you can define a role and influence them on user . For instance:
 <tomcat-users> <role rolename="admin"/> <role rolename="admin-gui"/> <role rolename="manager"/> <role rolename="manager-gui"/> <user username="name" password="pwd" roles="admin,admin-gui,manager,manager-gui"/> </tomcat-users> 
Note:
You may not have the default username and password defined here, so it is always useful to take the time to complete this configuration or you will encounter a problem when using Tomcat integrated into the IDE, such as NetBeans. In fact, these credentials will be required to use them correctly.
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