Cannot Send SMTP Outbound Mail Through ISA Server (811084)

RESOLUTION

1. Start the ISA Management snap-in: click Start, point to Programs, point to Microsoft ISA Server, and then click ISA Management.
2. Expand Servers and Arrays, expand your server, expand Access Policy, right-click IP Packet Filters, point to New, and then click Filter.
3. In the IP packet filter name box, type a descriptive name for the packet filter (for example, type Allow SMTP outbound), and then click Next.
4. Click Allow packet transmission if it is not already selected, and then click Next.
5. Click Custom, and then click Next.
6. In the IP protocol list, click TCP.
7. In the Direction list, click Outbound.
8. In the Local port list, click All ports if it is not already selected, click Fixed port in the Remote port list, type 25 in the Port number box that corresponds to the remote port, and then click Next.
9. Under Apply this packet filter to, keep the default selection of Default IP addresses for each external interface on the ISA Server computer unless you have more than one IP address or external interface on the ISA Server. If you have more than one IP address assigned or more than one external interface, you may want to specify the ISA Server's external IP address. To do this, click This ISA server's external IP address, and then type the IP address.
10. Click Next.
11. Under Apply this packet filter to, keep the default selection of All remote computers if your Exchange Server is configured to send mail directly to foreign messaging systems, or if you want to specify a particular smart host, click Only this remote computer, and then type the public IP address of the destination computer.
12. Click Next, and then click Finish.