启动SpringBoot项目报错?报错

Error starting ApplicationContext. To display the conditions report re-run your application with 'debug' enabled.
2019-04-30 17:24:49.049 ERROR [manage-backend,,,] 15816 --- [           main] o.s.b.d.LoggingFailureAnalysisReporter   :

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APPLICATION FAILED TO START
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Description:

Parameter 1 of method mailNotifier in de.codecentric.boot.admin.server.config.AdminServerNotifierAutoConfiguration$MailNotifierConfiguration required a bean of type 'de.codecentric.boot.admin.server.domain.entities.InstanceRepository' that could not be found.
    - Bean method 'instanceRepository' not loaded because @ConditionalOnBean (types: de.codecentric.boot.admin.server.config.AdminServerMarkerConfiguration$Marker; SearchStrategy: all) did not find any beans of type de.codecentric.boot.admin.server.config.AdminServerMarkerConfiguration$Marker

Action:

Consider revisiting the entries above or defining a bean of type 'de.codecentric.boot.admin.server.domain.entities.InstanceRepository' in your configuration.

Disconnected from the target VM, address: '127.0.0.1:52072', transport: 'socket'

Process finished with exit code 1