10.8. Controlling Anonymous Address Resolution
Problem
You want to reduce the possibility of outside parties spoofing sender addresses.
Solution
Using a graphical user interface to control address expansion in Exchange 2000
Open the Registry Editor (regedit.exe).
Navigate to:
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\MSExchangeTransport If the
Parameterssubkey exists, select it. If not, right-clickMSExchangeTransportand select New→ Key.Each SMTP virtual server has its own subkey under the
Parameterskey corresponding to its ordinal number. For servers with only 1 SMTP virtual server, this subkey will be named 1. If no key exists for the virtual server that accepts your inbound Internet mail, right-click theParameterskey and select New→ Key to add it.Right-click the SMTP virtual server key and select New→ DWORD Value to create a new value named
ResolveP2. Give it the appropriate flag value:0x08Tells Exchange to resolve the From header in incoming mail
0x10Tells Exchange to resolve the To and CC header fields
0x20Tells Exchange to resolve the Reply-To field
By default, Exchange will attempt to resolve all these headers, but by changing the flag value you can force it to ignore certain headers.
Quit the Registry Editor.
Stop and restart the SMTP virtual server to which you added this key.
To set the ResolveP2 flag in Exchange Server 2003:
Launch the Exchange System Manager (Exchange System Manager.msc).
In the left pane, expand the appropriate Administrative Groups container, and ...