How to return errors from a web service with Elmah?

In my WCF web service I use Elmah to protect against unhandled errors and it works great. However, when error happens the caller of the endpoint gets this response:

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How can I send the actual unhandled error that Elmah is recording back to the user?

Solution

ELMAH doesn't protect against unhandled errors, it just logs when they are happening. The Request Error page shown in the browser is WCfs way of telling you that an error happened. You don't want to publish error details like cookies and stacktrace to the client. Use /elmah.axd to see all of the details of each error.