Setup: MS Windows Server 2003 (domain controller)Exchange Server 2007Both hosted on the same machine, we only have 1 server. Several internal (on Exchange server) email accounts and several external (SMTP) contacts. Some users (and contacts) are members of multiple security groups. Each group is a member of a megagroup called "Staff". Charles is a member of Leadership, Membership, and Skills.Jennifer is a member of Business, Outside, and Recruitment.Each group is a member of Staff. If I send an email to Staff, Exchange server should break it down to the invidual emails and elimate duplicates. It does this for mailboxes hosted on the server, but external emails receive duplicates (randomly from 2 to 4 copies). As an example: 1) Staff email would be broken down as2) Business, Leadership, Membership, Outside, Recruitment, and Skills. Further broken down as3) Jennifer, Charles, Charles, Jennifer, Jennifer, Charles. Which should result finally in email to4) Jennifer, Charles. Instead step 3 winds up at step 4 as4) Jennifer, Charles, Jennifer, Jennifer If I send an email directly to Jennifer, she only gets it once. If I send an email to Business and Outside, Jennifer only gets it once. It seems as though the Exchange server is only breaking down external contacts once rather than all the way to individuals (which it does do for internal emails). As an aside, I did install and uninstall the SMTP role on the Windows Server 2003 after Exchange was installed. I read somewhere doing this would break the SMTP for Exchange and require the running of SMTPReinstall.exe to fix. This pointed to earlier versions than 2007 though, and it doesn't seem to apply any longer. Further I can't check the Exchange CD because I don't have one. We needed to get an Exchange server up now, so we opted for the 2007 demo until we could aquire a volume license from our vendor. We're a government office and it'll take a couple of months for the paperwork. If anyone can give me any help on this matter, I would really appreciate it.

Please, if anyone has any help on this matter, I would really appreciate it. I just spent all night uninstalling the Exchange server and reinstalling it. Hoping that would reset something. But alas, nothing. :( Still sends out duplicate emails when the receipiant is an external email. But only when done through groups. Sending email directly to the address doesn't cause this problem.

Here's some more information. Hopefully someone out there has an answer.I really think this is a bug of some sort. I have security groups setup for access control on the network. I based the groups on departments, but some users are members of multiple departments. I then enabled each security group in Exchange as a distribution group (may have the exact term wrong as Im not near the server right now, just set it so each security group could receive mail and then it sends a copy to each member of the group). Since we have Public users and Staff users, I created a Staff security group which includes all the department goups. This enables easiest management of users, groups, and resources. Some staff members are not users on our domain since they work for a different organization and use that orgs network, however they do work in our building and are considered equal staff (they just have no access to our resources). To allow security groups to be used for email distribution rather than having to maintain a totally seperate list of users, I created contacts for these other people. I then assigned these contacts to the security group they belong to. As such I cannot list their external email on an AD user object. So I have AD user objects with Exchange mailboxes and AD contact objects with external email addresses defined. I have multiple security groups consisting of both types of objects. All objects are members of more than one group. Theres one supergroup that consists of all the groups as well. If I send email to a users Exchange mailbox or to the contacts external email, everyone gets only 1 copy. If I send email to one group, everyone gets 1 copy. If I send email to more than one group at a time, Exchange users get 1 copy while external contacts get multiple copies. If I send email to the supergroup, Exchange users get 1 copy while external contacts get multiple copies. (The numbers of copies do not relate to the number of groups an external contact is a member of, the number of copies appears to be random.) Since the Exchange users are not getting duplicates (the Exchange server properly resolves the grouping down to invidividual users), yet the external contacts are getting multiple copies, I think something is wrong with either the Exchange servers resolution system or a setting I set. Any ideas? I dont think setting up a totally seperate distribution grouping as this defeats the purpose of the network/AD layout. Additionally what if I do setup multiple distribution groups, and a user sends email to more than 1 group, the contact would still receive multiple copies. I could be very wrong though, as Ive only been using Exchange server for about 2 months and am far from an expert on the matter.

Here's a message tracking log. First one is sending to a group which contains 2 other groups. 2 external contacts are members of each group. Next one is sending to another group which contains 2 other groups, 2 internal (Exchange) mailbox users are members of each group. (Posting it as a code block since it's wide, hopefully will format correctly.) EventID Source SourceContext MessageID Receipients InternalMessageID ServerHostName ConnectorID RecipientStatus TotalBytes RecipientCount RelatedRecipientsAddress Reference Receive Storedriver CCBD SuperGroup 2154 Local MX 6549 1 (null) Expand Routing Local MX CCBD SubGroup1, SubGroup2 2154 Local MX 250 2.1.5 RESOLVER.GRP.Expanded; distribution list expanded 6549 2 SuperGroup (null) Expand Routing Local MX CCBD User1, User2 2154 Local MX 250 2.1.5 RESOLVER.GRP.Expanded; distribution list expanded 6549 2 Group2 (null) Expand Routing Local MX CCBD User1, User2 2154 Local MX 250 2.1.5 RESOLVER.GRP.Expanded; distribution list expanded 6549 2 Group1 (null) Transfer Routing ContentConversion CCBD User1, User2, User1, User2 2155 Local MX 5126 4 2154 Transfer Routing Resolver CCBD User1, User2, User1, User2 2156 Destination MX SMTP 5170 4 2155 Send SMTP 08CB9DeC6F5F86AB CCBD User1, User2, User1, User2 2156 Local MX 250 2.1.5 (Users1 and 2 showing up twice) recipient okay 5170 4 Submit StoreDriver MBD, Event 5620 CCBD (null) (null) (null) Just Exchange EventID Source SourceContext MessageId Receipients InternalMessageId ServerHostName ConnectorId RecipientStatus TotalBytes RecipientCount RelatedRecipientAddress Reference Receive StoreDriver CCE9 SuperGroup Z 2851 Local MX 6533 1 (null) Expand Routing Local MX CCE9 SubGroup X, SubGroup Y 2851 Local MX 250 2.1.5 RESOLVER.GRP.Expanded; distribution list expanded 6533 2 SuperGroup Z (null) Expand Routing Local MX CCE9 User A, User B 2851 Local MX 250 2.1.5 RESOLVER.GRP.Expanded; distribution list expanded 6533 2 SubGroup Y (null) Expand Routing Local MX CCE9 User A, User B 2851 Local MX 250 2.1.5 RESOLVER.GRP.Expanded; distribution list expanded 6533 2 SubGroup X (null) Transfer Routing Resolver CCE9 User A, User B, User A, User B 2852 Local MX 6705 4 2851 Deliver StoreDriver CCE9 User A, User B 2852 Local MX 6705 2 (null) Duplicate StoreDriver CCE9 User A, User B 2852 Local MX 6705 2 (null) Submit StoreDriver MBD, Event 10434 CCE9 (null) (null) (null) Hopefully someone can help. :(