New Relic's .NET agent reports handled errors as though they are standard errors. This is most common with Azure worker roles, console apps, async work, and similar operations.
To avoid false error reports, instrument a method that directly or indirectly contains the exception handler. Instrument the target method by defining a custom instrumentation file, or by wrapping the method in a custom transaction, as shown in this example:
The only errors New Relic's .NET agent reports are unhandled errors that end a transaction. If your app calls an exception handler before the transaction ends, New Relic will not report an error.
However, New Relic does not always detect exception handlers when the error occurs outside of a web transaction, WCF transaction, or custom transaction. This is because the agent creates "mini-transactions" for instrumented methods that are not associated with a transaction.
When the instrumented method exits, the mini-transaction ends. If the mini-transaction throws an error and the instrumented method does not handle it, then New Relic will report an error.
You can see this in a console app that calls
GetResponse(), as shown in the example. If
GetResponse throws an error, then New Relic will report it, even though
GetResponse() is called within a try/catch block. The agent reports an error because the
GetResponse() "mini-transaction" ended and the error was still unhandled on transaction exit.