Outlook 2016 Search Function Not Working on Shared Mailboxes

You discover that the search function in Outlook returns no results when searching a shared mailbox, yet it works fine in your primary mailbox.

You've even tried to delete your profile and re-create it and still the problem persists.

Before we start the rectification process, please ensure you have killed off your instance of Teams, Skype and any other Office application for good measure through Task Manager. Some of these applications will prevent the changes to the OST file we'll need to do later on in this tutorial. Thanks to NoUfixItForMe in the comments below for his/her contribution. I have tested this and can confirm this rectified preventing the change applying permanently to the OST file.

So how do you fix it?

Firstly, we need to disable the the indexing on Outlook by going to File > Options > Search and the click Indexing Options. Now follow the screen shots below:

Now that we've done that, close Outlook and any email windows you have open. Open Control Panel and ensure in the View By drop down list at the top of the window is set for Small Icons to display the full contents of the Control Panel.

Click on the Mail (32-bit) link to open the Mail Setup of Outlook. Now follow the screen shots below:

Click OK through all the windows to apply the changes. Now we're going to re-enable the indexing function in Outlook so these changes will be picked up. Open Outlook and then go to to File > Options > Search and the click Indexing Options. Now follow the screen shots below:

You've now completed the rectification process. Now try and search the shared mailbox and all should be good. It may be a bit slow to search initially, due to the indexing that is being carried out in the background. Depending on how large your email file is, it could take a few hours to complete the indexing task. Once the indexing is complete the speed of your search should improve dramatically.

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16 Responses

  1. Unfortunately the "allow this file to have contents indexed in addition to file properties" unticks itself
    • Matrix7
      Hi Nick, Do you have permissions to edit the file? Ensure the correct permissions are applied and then try again...
  2. For the most part this seemed to have worked. Thanks for the article!
  3. I have been having this problem for months now. I followed your process. It was simple to follow and it fixed my issue! I'm hoping that it sticks. In the past the rebuilding the index would work for awhile and then I'd be back to the same problem. Fingers crossed! Thank you for the help!
  4. Thanks :D worked first try
  5. Seemed to work but soon had the problem return. And I've similarly noticed the box becoming 'unticked' again (when I fire up Outlook). Having tried 2-3 other fixes suggested elsewhere (e.g. DisableServerSearch reg entry, also deleting the OST/NST files and allowing Outlook to recreate them) I found a Microsoft tech community thread which suggests the problem is an acknowledged bug but which Microsoft doesn't seem to be getting round to fixing. The same thread suggested a workaround (disable shared folder downloads) which seems to have overcome the issue for me; I'm running with it in hope there'll be no colateral damage, as it were, from the workaround. https://techcommunity.microsoft.com/t5/outlook/search-in-outlook-2016-shared-mailbox-is-not-working/m-p/133279/page/6
    • Matrix7
      Hi Simon, I haven't experienced the issue returning on any of our clients that we've applied this fix to. Funnily someone else has posted that their issue returned as well. Did you check the properties of your OST file? Has the setting reverted, or has the search indexing simply stopped working? Would be interesting too know...
  6. I've been getting this problem too. I've ticked the box, it didn't fix my issue and it just keeps getting unticked after a while.
    • I might have a solution for the Index property of the .OST file. Two other MS applications use this file. Teams and Skype if those apps are running ANY changes I do to the .OST file will not hold. So check in Task Manager for Teams or Skype and task kill them.
      • Matrix7
        Thanks for the suggestion. I'll include your contribution in the post and credit you... Thanks
  7. Anyone know if this still works today? Has a recent update from MS broken this process? I've used this article before to accomplish the desired result but can't seem to recreate the result using the same steps above, even after closing other MS Office background processes.
    • Matrix7
      What is not working for you? Is the Allow to Search the Contents setting not holding?
      • Sorry should have added context. I'm able to go up to the last step but the tickbox "Allow files in this folder to have contents indexed in addition to file properties" always seems to untick itself despite having no other MS office app open. Any ideas?
        • Matrix7
          Did you kill all the MS services like Teams, Skype, Word Excel and essentially any other Office application? If so, maybe do a reboot, don't open any applications open task manager and kill off any application that auto starts. Then try a carry out the process without opening Outlook and do it through Control Panel > Indexing Options
          • Tried doing the above, on a (relatively) clean machine build. Restarted, closed any MS products which may open on startup. Carried out the process through cpanel but the 2nd tickbox "Allow this file to have contents..." still unticks itself seemingly the moment I try and select Outlook as an indexed location.
          • Matrix7
            What permissions do you have on the OST file? Navigate to the OST file, right click and select Properties. Click on the Security tab highlight your username and ensure you have Full Control over the file.

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