Outlook 2016 on Terminal Server (Online Mode) and Search

Question

Hello,

I'm facing a strange issue with Outlook Search on Terminal Server.

I have Outlook 2016 running on RDS Farm in Online Mode (as Best Practice) and Windows Search on the Session Host server is disabled (again, as Best Practice). I have Exchange on-premise.

Basically this is what I'm experiencing:

• Search from OWA: everything works as expected.

If I type "From:Andrea.Gaviraghi" in Search box, search correctly returns all emails received from Andrea.Gaviraghi;

• Search from Outlook by using Advanced Search: everything works as expected.

If I type "Andrea.Gaviraghi" in the "From:" field, search correctly returns all emails received from Andrea.Gaviraghi;

• Search from Outllok by using "normal" Search box: search is not working and I get mixed results.

If I type "From:Andrea.Gaviraghi" in Search box, search returns a lot of emails, even if not received by "Andrea.Gaviraghi".

Seems like it also looks into the body, so if I have an email sent by another user in reply to one email I sent to him, I see his email as in the body there is From:Andrea.Gaviraghi etc...

After digging into the issue I tried to start the "Windows Search" service and with the service running Outlook "normal" Search also works as expected.

As Outlook is running in Online Mode, no .ost file is present locally on the Session Host server and thus I don't understand how and why "Windows Search" helps here.

I read a lot of articles but didn't find anything that explain tis behavior.

Hope someone sheds some light on this helping me.

Thank you.

Andrea

Answer 1

Hello @Jade Liang-MSFT,
thanks for your email.

If I simply type "Gaviraghi" as search term (using "Normal" search box within Outlook and not the "Advanced Find") I get a lot of results but of course also emails I'm not looking for.

If I just want to search for all emails received from "Andrea Gaviraghi" (selecting "Current Mailbox" as Search Scope) it's impossible with the "Normal" search box. I have to use "Advanced Find".
If it's by design it would be good to have this written in some articles.

Regarding the "Natural Language Queries" I followed what's written in the article:

"For example, Outlook supports the use of natural language queries, such as received:this year. However, Outlook FAST search does not. Therefore, if you submit received:this year, Outlook automatically displays WDS search results. To use FAST search for a similar query, you would need to submit the following criteria: received>12/31/2016"

If I search "received:this year" I get mixed results, also from previous years;
But the same occurs if I search "Received> 01/01/2021" as I still get mixed results, also from previous years;

I also read this:

"To recap, Outlook uses FAST search and/or returns results using FAST, except if any one of the following conditions are true:
-Outlook is connected to the mailbox in online mode;"

This is my scenario as I'm running Outlook 2016 in Online Mode with my mailbox on Exchange 2019 server (OnPrem).
To recap: based on my own research/experience if Outlook is running in Online Mode the only way to get trusted/reliable results is to user the "Advanced Find".

Again, if this is by design ok, but please MS write this somewhere!

Thanks,
Andrea Gaviraghi

Answer 2

Hi @Andrea Gaviraghi ,
Welcome to our forum.

Search from Outllok by using "normal" Search box: search is not working and I get mixed results.

For your issue, I have tried to disable windows search and search in online mode on my Outlook 2016 for testing, and found it indeed couldn't work normally, which is same with your issue. Actuallly, as I know, the "normal" search box--instant search function in outlook, which actually depends on windows search, and it may cause many issues when windows search is disabled or corrupted, here are many general issues for outlook search: Troubleshooting Outlook search issues
Also, I have searched in the point of windows search index and found "Outlook uses it to search your email" in the field of "Which apps use the index?". So I think it's normal that we couldn't search normally in Outlook when we disabled the windows search.

Hope that would be helpful to you.

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Answer 3

Hello @Jade Liang-MSFT,
first of all thanks for your feedback.

There are still several things I don't understand, for example:

• if Outlook is running in Online Mode I don't understand how "Windows Search" service can improve search results as no .ost file is created locally;
• As soon as I start the "Windows Search" service, Outlook search works perfectly but the service didn't indexed any emails of course as Outlook is running in Online Mode;
• Maybe I'm wrong but as far as I know if Outlook is running in Online Mode Outlook uses Exchange index for searching (exactly as OWA);
• From what I read here:
  https://social.technet.microsoft.com/Forums/office/en-US/fc2d5e48-ec7d-4673-933b-488f7c608fee/outlook-2016-on-terminal-server-windows-search-disabled "When running in Online Exchange mode, Windows Search cannot crawl and index e-mails locally. All searching are performed based on the Exchange index"

I'm confused.
Thanks,

Andrea

Answer 4

Hello @Jade Liang-MSFT,
thank you very much for your email.

I still don't understand why the Advanced Find works without any issue as it correctly returns all email based on my search criteria.
Is there a way to force the Advanced Find?
Or is not possible/recommended as this kind of search only relies on Exchange thus loading too much the server?

Thanks,
Andrea