a.	In the Services snap-in, click Start, click Run, type services.msc, and then click OK.
b.	Right-click Microsoft Exchange Routing Engine, and then click Stop.
c.	Right-click Microsoft Exchange Routing Engine, and then click Start.
d.	Right-click Simple Mail Transport Protocol (SMTP), and then click Stop.
e.	Right-click Simple Mail Transport Protocol (SMTP), and then click Start.
f.	Exit the Services snap-in.

After you configure these settings, Exchange can forward messages to a foreign messaging system that shares the same SMTP domain name space.