Getting Started with ThingWorx > Installing and Upgrading ThingWorx > Licensing Troubleshooting
  
Licensing Troubleshooting
Fetching a License from FNO
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It is only recommended to enable logging debugging if you are troubleshooting Active Directory authentication issues. These messages are logged in the Application Log, and can cause the log to get flooded when enabled.
You can enable debug logging to troubleshoot problems retrieving a license file from the license server. To enable debug logging, use a standard logback.xml file in the ThingworxPlatform directory. If a logback.xml file exists in this location, you can add the licensing logger to the existing set of loggers.
<configuration>
<logger name="com.thingworx.system.subsystems.licensing.LicenseFetcher" level="DEBUG"/>
</configuration>
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The logback.xml functionality is a Java standard. For instructions about configuring these files, refer to Java documentation.
The following information about the logger package will help to investigate problems related to the connection between the ThingWorx Platform and the license server.
Package:
com.thingworx.system.subsystems.licensing.LicenseFetcher
Entry:
<logger name="com.thingworx.system.subsystems.licensing" level="DEBUG"/>
Description:
With debugging enabled, here are example logs that will show up in the Application Log:
1) Invalid License Server URL:
[L: ERROR] [O: c.t.s.s.l.LicensingStateMachine] [I: ] [U: SuperUser] [S: ] [T: localhost-startStop-1] Unable to retrieve license from FNO server because invalid.ptc.com: Name or service not known
2) Invalid License Credentials:
[L: DEBUG] [O: c.t.s.s.l.LicenseFetcher] [I: ] [U: SuperUser] [S: ] [T: localhost-startStop-1] Failed authenticating to license server
[L: INFO] [O: c.t.s.s.l.LicenseFetcher] [I: ] [U: SuperUser] [S: ] [T: localhost-startStop-1] Unable to retrieve License capabilities from license server
3) Valid License Credentials:
[L: DEBUG] [O: c.t.s.s.l.LicenseFetcher] [I: ] [U: SuperUser] [S: ] [T: localhost-startStop-1] Successfully authenticated to license Server