To get a verbose log from WCF, you can add this section to C:\Program Files (x86)\SolarWinds\Orion\Information Service\3.0\SolarWinds.InformationService.Service.exe.config:
<source name="System.ServiceModel" propagateActivity="true" switchValue="Information, ActivityTracing">
<add initializeData="c:\Logs\SWISv3.svclog" name="traceListener" type="System.Diagnostics.XmlWriterTraceListener"/>
This can be just inside the </configuration> tag at the end of the file. You will need to restart SolarWinds Information Service V3 after making this change. If possible, I recommend having all other services stopped while you troubleshoot this issue. The .svclog file will grow very quickly if the system is active, so debugging will be easiest if you have as few calls as possible happen while this level of tracing is active.
To whom may concern,
This issue happened again in our 'Production', there are no changes to our environment, it just began to return 403 from yesterday (07-01) afternoon. Restarting the service doesn't help. I have enabled WCF logging, but can not find any leads from the svclog.
Once before we used a walk around solution which is by setting 'SolarWinds Information Servcie V3's 'log on as' to a domain service account instead of 'Local system account'. This walk around works fine until yesterday. Since our walk around doesn't work anymore, we switched back to using 'Local system account' as you suggested, so shall we continue solving this 403 forbidden issue?
It is quite urgent, that is our 'Production' environment.