There are a few reasons why you may not be able to enable EUM:
1. “Configure EUM” permissions
If you don’t have the “Configure EUM” permission, you won’t be able to configure Browser and Mobile RUM. You can set EUM permissions for custom roles from the Applications tab in the Controller Administration UI. For instructions on how to assign this application permission to a role, see: Application Permissions.
2. EUM application naming
Starting in version 4.3 onwards, you cannot enable EUM in an APM application like you used to do in version 4.2 and earlier from the Configurations > End User Monitoring > Instrumentation screen. Now, enabling and disabling EUM applications can only be done from the EUM Application > Configuration > Instrumentation page in the UI. Additionally, you cannot create an EUM application with the same name as an existing APM application. AppDynamics separated the EUM application from the APM application, so you need to create an EUM application with a different name for a related APM application under the 'User Experience' tab in the Controller UI. For more information, see: APM and EUM application separation in AppDynamics version 4.3
3. Communication Issues
If the Controller is experiencing communication issues with the EUM server, the ability to enable or disable EUM will be blocked. These issues include internal server errors, SSL certificate errors, connection refused errors, and 401 auth errors. To review the list of communication issues and how to resolve them, review our guide on Connection Issues related to EUM.