Outlook could take 50% CPU

Posted on 2011-04-21
Last Modified: 2012-05-11
I have a problem with outlook 2007.
When adding an exchange account for first time in outlook 2007 i notice that it uses 50% cpu usage.
Even when it finish the updating the inbox etc.
Any idea what causes this problem?

Question by:christosskl
    LVL 17

    Expert Comment

    First, I would start with running Office Diagnostics.  For Outlook, it is under Help > Run Diagnostics.

    Second, is the account using Exchange cached mode?  If it is, turn it off then restart Outlook.  If the problem goes away, try to turn it back on and see if the CPU usage issue comes back.

        On the Tools menu, click Account Settings.
        On the E-mail tab, click the Exchange Server account, and then click Change.
        Under Microsoft Exchange server, select the Use Cached Exchange Mode check box.
        Exit and restart Office Outlook 2007.

    Third, does the 50% CPU usage happen when logging in as a different user on that machine and setting up an exchange account under that user?


    Author Comment

    I will try all the above and i will let you know.
    Thank you for your answer.

    Author Comment

    Good morning

    The Run Diagnostics found no problem.
    With the cached mode there no change at all.
    When i logon with onother user and create a exchange account there is no problem with the outlook.
    So the problem happens only in the specific user in the specific computer.

    Any other idea?
    LVL 17

    Expert Comment

    I see.  A couple other things, I assume this is on Active Directory.

    1. How large is the mailbox for the problem user?  Larger mailboxes will take time to download into cache and cause high CPU usage, but only until all items are downloaded and synced.

    2. Can the problem user log on to a different computer, setup the email account and reproduce the 50% issue?  If the same issue happens for that user on a different computer, then the issue likely lies at the server, not Outlook.

    Let me know so I can determine what approach to take next.

    Author Comment

    Good morning

    No the mailbox is small.
    And in a different computer the mailbox has no problem.
    So i suppose that something happen with the specific computer.

    LVL 17

    Expert Comment

    Hello, thanks for the update.

    What I would suggest at this point, is backup that user's data (e.g. Desktop, Documents, Favorites, and Cookies), delete their profile from the problem computer.  Log on with a fresh account and re-setup the Outlook account.  Is the OS Windows XP?  If so:

    1. Login as an Administrator.
    2. Right-click on My Computer and select Properties.
    3. Select the Advanced tab, and then click Settings under User Profiles.
    4.  Highlight the problem user's account and then delete it.
    5. Reboot the computer.

    This will clear their profile from the machine.  Then, log in as the problem user.  Before restoring their data, setup the Outlook account first and confirm whether or not the issue is resolved.  If it is, restore their data and check Outlook one more time to be sure.

    One thing to consider, if you cannot delete their profile per step 4, then the registry has not unloaded the profile yet.  In this case, download the User profile hive cleanup tool from Microsoft's website.

    If the above still fails, check the Event Viewer under Administrative Tools for any events related to Outlook.
    LVL 17

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