How to see localhost traffic in fiddler? (Show local IIS traffic in fiddler)

If one of your applications in your IIS is calling another application within your IIS, fiddler doesn't catch it by default. To show that traffic you need to perform two simple steps

1>In your config files, replace localhost/ with yourMachineName/
2>Run all IIS application pools under the same id that is running fiddler.(Note: If one of the apps inside IIS is calling another app in IIS. And the caller is running under an identity different from the identity that fiddler is running under, then that call will NOT be logged. )

What I usually do for testing is run all the application pools under my userid.