Your network contains a single ISA Server 2006 computer, which is named ISA1. ISA1 provides access to the Internet for computers on the Internal network, which consists of a single subnet.
The companys written security policy states that the ISA Server logs must record the user name for all outbound Internet access. All client computers are configured with the Firewall client and the Web Proxy client and are not configured with a default gateway. Users in the marketing department require access to an external POP3 and SMTP mail server so that they can use an alternate e-mail address when they sign up for subscriptions on competitors Web sites.
You create and apply an ISA Server access rule as shown in the following display.
The marketing department users configure Microsoft Outlook to connect to the external mail server.
They report that they receive error messages when they attempt to read or send e-mail from the external mail server. You examine the ISA1 logs and discover that ISA1 denies POP3 and SMTP connections from the client computers.
You need to ensure that the marketing department users can connect to the external mail server.
What should you do?

A.
Configure the marketing computers with the IP address of a DNS server that can resolve external names to IP addresses.

B.
Configure the marketing computers with a default gateway address that corresponds to the IP address of ISA1 on the Internal network.

C.
On ISA1, enable Outlook in the Firewall client settings.

D.
On ISA1, create a computer set that contains the marketing computers.