Starting in v22.0.0 of the Ads API .NET library, SOAP backend has been upgraded from System.Web.Services to System.ServiceModel (WCF). As a result, SOAP extensions are no longer used for logging. You can still configure your logging settings through the system.diagnostics section of the App.config. If you need similar behavior to the SOAP extension, you can create a custom
IClientMessageInspector and apply it to the service instead. Please see this
guide for more details.
Shwetha, AdWords API Team.