private void ValidateAddress(string address, string attributeName) { if (this.config.MembersAsNonReference) { return; } if (attributeName.StartsWith("external")) { if (GroupMembership.IsAddressInternal(address)) { throw new UnexpectedDataException($"The value {address} cannot be exported as {attributeName} as it is a known internal domain. It should be exported as {attributeName.Replace("external", string.Empty)}"); } } else { if (GroupMembership.IsAddressExternal(address)) { throw new UnexpectedDataException($"The value {address} cannot be exported as {attributeName} as it is not a known internal domain. It should be exported as external{attributeName}"); } } }