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What about the OAL Generator events I see on my Exchange servers? (Event ID 9325 – OAL Generator)

(Looks like this is not documented in detail elsewhere)

Of late, one user rang me and said she is not able to see her Team’s DL created on Exchange server. I thought it might be an Outlook related issue and instructed my team to investigate on it. After about 2 hours, my team came back with blank faces! The point to note is that this user is very recently migrated from Exchange 2003 to Exchange 2010 (Exchange 2010 was very recently deployed here). Surprised, I started my investigations. Connecting to the user’s desktop, I ran some checks on Outlook (Cached/non-cached mode) and nothing helped.

I checked the Application logs of Exchange 2003 OAB server and found something that would interest any Administrator:

Event Type: Error
Event Source: MSExchangeSA
Event Category: OAL Generator
Event ID: 9325
OALGen will skip user entry ‘Display Name’ in address list ‘Global Address
List’ because the SMTP address ” is invalid.
– Default Offline Address List

Bing and Google are my lifelines in crazy scenarios of such nature! But they let me down for much of the search results were pointing to Exchange 2007 and surprisingly, we don’t have any Exchange 2007 in our infrastructure. Someone even related this to Exchange 2010 we have. Checking the CAS logs, and I found logs of similar nature announcing that CAS is unable to process these entries.

After a bit digging with no avail, I gave up and thought Microsoft might help me (Ever used the the link in the event that says For more information, see Help and Support at: The page for this event is here.

And surprisingly, I wasn’t cheated this time! 🙂 The following is an extract from the site:

This Error event indicates that the user account specified in the event description has not been included in an offline address list because of an incorrectly configured SMTP address. For example, an incorrectly configured SMTP address is an address that contains a dash “-“, an underscore “_”, or no characters after the @ symbol. Incorrectly configured SMTP addresses can occur in the following circumstances:

-> A script modified either a user’s primary SMTP proxy address attribute or e-mail address attribute. These attributes must match for a user to be added to an offline address list.

-> An administrator modified the e-mail address of a user on a computer that did not have the Exadmin.dll extensions loaded.

Ignorance can be a Bliss at times or a Curse otherwise!!

We have our L1 Help Desk team to create and manage Accounts & DLs and after the implementation of Exchange 2010 in the organization, they are asked to use Windows 2008 R2 servers for Administrative tasks that have only Exchange 2010 tools and Active Directory Management tools. I learnt that they made changes to DLs e-mail address using Active Directory Users and Computers like they usually did on for Exchange 2003 (no more Exchange related tabs on new servers and since “E-mail address” tab is missing, they made the changes to “General” tab thinking that it will take effect). Luckily, I had only few of the DLs reported and so, I quickly went and added the e-mail address in “General” tab as an additional SMTP Address.


For folks who discover it too late, OAB Integ might help you! See Microsoft  KB907792.

If one of you ever had a chance to see this event, and find something else as the cause, comment here so that it might help others!


6 Responses to “What about the OAL Generator events I see on my Exchange servers? (Event ID 9325 – OAL Generator)”

  1. Shambhu Says:

    Hello Muthu,
    This is normal for any exchange administrator as I had experienced same problem lot of time and tried to teach SD or Level 1 engineer to fix problem using the exchange management console at “email addresses” tab of user’s properties (It seems you are repeating the same task as service desk did: – “I quickly went and added the e-mail address in “General” tab as an additional SMTP Address.”) There are no options at AD/exchange server that you can add the additional email addresses in “General Tab”, you can do it only using from Exchange Management Console or Exchange Management Shell at “Email Addresses” tab. I am not sure about ADSI Edit as it depends on AD but it is also point to exchange features so you could modify from here also.
    There are lot of other problem could happen for this type of event and that could be give the other error and as well your mentioned error; like 1) two same email addresses existing for two different users. 2) As mentioned in alert that after @ sign ( there could some wrong character has input or 3) some time if the two different users (mailbox and mail user) have same login ID in same domain. (All above error could not be made by human; it should be by automated application that pushes this information at AD and exchange.)

  2. Muthukumar P Says:


    I agree with you! The intention of this article is to help the admins dependent on search engines and found nothing regarding their issue.

    I see your points as very valid, and just to assist someone else looking for assistance on similar points, I’d like to add more to your lines:

    As on coming to modifying the General attributes, any admin prefers to modify it using GUI/PowerShell though ADSI Edit is always there to present unnecessary attributes and confuse us.

    As for the reasons you specified:

    1. Agreed that the presence duplicate SMTP addresses can be the cause. In that case, event logs clearly shows the duplication of SMTP address. Also while attempting to re-use the existing SMTP address, your GUI/Powershell would anyway present a sensible error and would prevent humans from encountering uncomfortable scnearios. The only culprit here would be scripts that would force adding the SMTP addresses no matter what!

    2. The invalid/wrong character again using a GUI/Powershell is quite impossible. In an event this occurs, the event details won’t say the SMTP address ” is invalid but would say the the SMTP address user! is invalid.

    3. Two different users having the same login ID in same domain: I’m not quite clear here. Can you please explain to me on what exactly this is and how this is possible?

    Though I do agree with your argument that few errors above are only made by applications, I still would disagree with the fact that humans are error proof when it comes to AD. (My & your SD guys are the best examples)


  3. Shambhu Sharma Says:

    Point third: I faced this problem in Exchange 2003 where I show Mailbox user and mail user got the same alias name (did not remember about domain loing ID) and due to this reason email address was also impected and user were getting non-delivery report.

  4. Muthukumar P Says:

    Strange. The first thing you would have to do is to fix the RUS (If these one of these two users or both users were supposed to be stamped automatically). In a real life scenario, the RUS would suffix the e-mail addresses by adding numbers to it.

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