A user recently asked one of our Help desk staff members to remove a few users from an existing Active Directory (AD) distribution list (DL) to create a new DL. Unfortunately, the DL was large and the Microsoft Management Console (MMC) Active Directory Users and Computers snap-in doesn't have a copy command for copying DLs. You can use the Comma Separated Value Data Exchange (CSVDE) or Lightweight Data Interchange Format Data Exchange (LDIFDE) command to copy DLs, but an easier method exists if you have Microsoft Office Outlook 2003 installed on the same machine as the Active Directory Users and Computers snap-in.
Open Outlook 2003 and create a new email message addressed to the DL you want to copy. Click the plus sign (+) that appears next to the DL. Clicking this symbol expands the DL and lets you see its members.
If the DL doesn't expand to show members, the membership is hidden. To unhide the membership, start the Active Directory Users and Computers snap-in, right-click the DL you want, and click Exchange Tasks. Click Next, Unhide Membership, Next. Finally, click Next, Finish.
You can then copy the DL's list of users. Copy the list into the member list dialog box you use to add new users to an AD group.