title: Unable to load config data from 'optional:configserver:http://localhost:8090 - SpringBoot 2.4.0 Illford 2020.0.0-M3
body: <p>Question regarding the new SpringBoot 2.4.0 please.</p>
  <p>First, we upgraded our Config Server and Config Client to SpringBoot 2.4.0 + Illford 2020.0.0-M3</p>
  <p>Then, we followed the &quot;new way&quot; of setting properties <a href="https://spring.io/blog/2020/08/14/config-file-processing-in-spring-boot-2-4" rel="nofollow noreferrer">https://spring.io/blog/2020/08/14/config-file-processing-in-spring-boot-2-4</a> and would like to stick with this new way.</p>
  <p>Hence, I configured this in our application.properties (please see <strong>the spring.config.import</strong> )</p>
  <pre><code>server.port=8010
  spring.application.name=mycoolservice
  spring.config.import=optional:configserver:${SPRING_CLOUD_CONFIG_URI:https://localhost:8090}/config
  </code></pre>
  <p>Then, we deleted our old but working bootstrap.properties</p>
  <pre><code>server.port=8010
  spring.application.name=mycoolservice
  spring.cloud.config.uri=${SPRING_CLOUD_CONFIG_URI:https://localhost:8090}/config
  spring.profiles.active=${SPRING_PROFILE_ACTIVE:local}
  </code></pre>
  <p>Finally, we started the app and observed:</p>
  <pre><code> ERROR [,,] 31987 --- [           main] o.s.boot.SpringApplication               : Application run failed
  
  java.lang.IllegalStateException: Unable to load config data from 'optional:configserver:https://localhost:8090/config'
      at org.springframework.boot.context.config.StandardConfigDataLocationResolver.getReferences(StandardConfigDataLocationResolver.java:124) ~[spring-boot-2.4.0.jar:2.4.0]
      at org.springframework.boot.context.config.StandardConfigDataLocationResolver.resolve(StandardConfigDataLocationResolver.java:111) ~[spring-boot-2.4.0.jar:2.4.0]
      at org.springframework.boot.context.config.ConfigDataLocationResolvers.lambda$resolve$1(ConfigDataLocationResolvers.java:114) ~[spring-boot-2.4.0.jar:2.4.0]
      at org.springframework.boot.context.config.ConfigDataLocationResolvers.resolve(ConfigDataLocationResolvers.java:125) ~[spring-boot-2.4.0.jar:2.4.0]
      at org.springframework.boot.context.config.ConfigDataLocationResolvers.resolve(ConfigDataLocationResolvers.java:114) ~[spring-boot-2.4.0.jar:2.4.0]
      at org.springframework.boot.context.config.ConfigDataLocationResolvers.resolve(ConfigDataLocationResolvers.java:106) ~[spring-boot-2.4.0.jar:2.4.0]
      at org.springframework.boot.context.config.ConfigDataImporter.resolve(ConfigDataImporter.java:101) ~[spring-boot-2.4.0.jar:2.4.0]
      at org.springframework.boot.context.config.ConfigDataImporter.resolve(ConfigDataImporter.java:93) ~[spring-boot-2.4.0.jar:2.4.0]
  
  
  Caused by: java.lang.IllegalStateException: File extension is not known to any PropertySourceLoader. If the location is meant to reference a directory, it must end in '/'
      at org.springframework.boot.context.config.StandardConfigDataLocationResolver.getReferencesForFile(StandardConfigDataLocationResolver.java:199) ~[spring-boot-2.4.0.jar:2.4.0]
      at org.springframework.boot.context.config.StandardConfigDataLocationResolver.getReferences(StandardConfigDataLocationResolver.java:121) ~[spring-boot-2.4.0.jar:2.4.0]
      ... 30 common frames omitted
  </code></pre>
  <p>What is the issue please?</p>
  <p>Thank you</p>