XADM: Unable to Resolve Distribution List from the Global Address List (246517)

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256986 Description of the Microsoft Windows Registry

SYMPTOMS

When a client tries to resolve a name and the organization created a distribution list (DL) with the name "SM," "SMT," or "SMTP" (without quotation marks), the client receives all users with an Simple Mail Transfer Protocol (SMTP) address from the Global Address List as possible candidates in the name resolution.

CAUSE

This problem occurs when an organization creates a mailbox or DL with the letters "SMTP" (without quotation marks) or a shortened version, such as "SMT," "SM," or "S" (without quotation marks).

WORKAROUND

WARNING: If you use Registry Editor incorrectly, you may cause serious problems that may require you to reinstall your operating system. Microsoft cannot guarantee that you can solve problems that result from using Registry Editor incorrectly. Use Registry Editor at your own risk.
To resolve this issue:

Click Start, click Run, and then type regedt32.exe.
Locate and click the following registry key: HKEY_LOCAL_MACHINE/System/CurrentControlSet/Services/MSExchangeDS/Parameters
On the Edit menu, click Add Value, and then add the following Value Name and Data Type:
Value Name: DSA Heuristics
Data Type: Reg_SZ
Click OK, type 00010 for the string value, and then click OK.

Follow these steps for each server in the organization.

NOTE: You must restart Directory Services for these changes to take effect.

MORE INFORMATION

Exchange interprets S, SMT, and SMTP as an improperly typed one-off addresses, and then presents the entire Global Address List for the recipient. If you set up a DL and users have aliases of SMT (SMTP), CCM (cc:Mail), PRO (Profs), SNA (SNADS), and not (Notes), it works in the same way. However, if you type =CCM in the To box, and then resolve the name, the name resolves to the correct address.