The caller was not authenticated by the service-for wcf service
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I have a running web application and it is using a wcf service ,now i need to deploy this service in different region, i have used 2 iis front end-server,where i have deployed application and in back-end sever  wcf service is deployed.
When i am trying to call api from application it is showing "caller is not authenticated by service", i guess this is not related to configuration setting because i have used same setting in many regions ,  it is some what related to iis(application pool).

last time i have also faced same issue while deploying service in a particular region then i changes application pool settings by hit and trail and it start working. but this time it not working.

Do wcf service needs any specific iis settings?