ReportServer -> The request failed with HTTP status 401: Unauthorized

I have a page that pulls a list of reports from our ReportServer and displays the list. It works fine when I view it both locally and within our domain, but when one of our testers from outside tries, the following error is generated when ListChildren() is called:  The request failed with HTTP status 401: Unauthorized
I'm using the following code, where the credential Username/Password/Domain are populated from textboxes:


Dim cred As New NetworkCredential("NetworkCredUsername", "NetworkCredPassword", "NetworkCredDomain") svcReporting.Credentials = cred svcReporting.PreAuthenticate = True Dim reportItems As CatalogItem() = svcReporting.ListChildren("/", False)I have also set <identity impersonate="true"/>


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