Share via

Windows 11 search indexing extremely slow on fast box, already tried every common recommendation

AdamKessel-0270 81 Reputation points
2025-06-25T11:03:28.01+00:00

I recently did an in-place upgrade from Windows 10 22H2 to Windows 11 Enterprise 24H2 (26100.4351) on two Lenovo boxes. In both cases, the search index was wiped by the process and indexing restarted from scratch. On my older box (a 2020 X1), indexing is progressing at a reasonable speed, between a few hundred and a few thousand entries added to the index per minute. On my newer box (a high-end 2025 P1G7, Intel Ultra 9 185H/2300MHz/16 Cores, NVIDIA GPU, 32GB RAM, 1TB SSD), indexing is going at a snail pace--often only one item per minute, maxing out at a few dozen per minute.

I'm on the latest Office 365 (Version 2507 Build 16.0.19009.20000). There are a few hundred thousand items in my Outlook store, which is the only thing that should be indexed. All mail is stored locally/offline, and Outlook shows all folders are 100% synced.

So far I've tried:

  • Windows Update
  • Lenovo Update
  • Intel Update
  • disable index backoff via registry key, reboot
New-Item -Path “HKLM:\SOFTWARE\Policies\Microsoft\Windows\Windows Search” -Force | Out-Null
New-ItemProperty -Path “HKLM:\SOFTWARE\Policies\Microsoft\Windows\Windows Search” -Name “DisableBackoff” -Value 1 -PropertyType DWORD -Force
  • rebuilding index from scratch, again
  • sfc /scannow
  • dism /Online /Cleanup-image /Restorehealth
  • deleting registry key [HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows Search\PluginResourceData], reboot
  • removing everything from indexing other than Outlook email
  • downloading latest Windows 11 Enterprise ISO, mounting, running setup.exe with option to keep applications and files in place
  • attempting to reset search this way:

dism /online /Disable-Feature /FeatureName:"SearchEngine-Client-Package"
reboot
rm C:\programdata\Microsoft\Search
reboot
dism /online /Enable-Feature /FeatureName:"SearchEngine-Client-Package"
reboot

None of these seem to have any impact on glacial indexing speed.

Anything else I can try to fix or at least further diagnose what is going on?

Windows for business | Windows Client for IT Pros | User experience | Other

7 answers

Sort by: Most helpful
Most helpful Newest Oldest
  1. Henry Mai 8,220 Reputation points Independent Advisor
    2025-06-27T01:26:24.7533333+00:00

    Hello AdamKessel-0270, I just wanted to share a quick insight about the issue.

    It looks like you identified the issue and resolved it perfectly on your own. The indexer was trying to crawl non-cached Public Folders over the network, and the real bottleneck wasn’t your local hardware but the network latency. That’s what caused the slow indexing.

    For future reference or if this comes up again after a profile rebuild, there’s a simpler, GUI-based way to exclude Public Folders without needing to use the API:

    • Open Control Panel > Indexing Options
    • Click the Modify button
    • In the "Indexed Locations" window, expand Microsoft Outlook
    • You’ll see a list of all mailboxes and data sources—just uncheck the top-level item labeled "Public Folders"

    This will exclude them from indexing via the interface, and it gets you the same result as your solution.

    Hope this helps!

    Was this answer helpful?

    1 person found this answer helpful.
  2. AdamKessel-0270 81 Reputation points
    2025-06-25T19:15:47.0666667+00:00

    I think I've found the problem. It appears the search indexer was indexing Public Folders in Outlook, which are not stored locally. It is nontrivial to disable indexing public folders -- as best I can tell, this can only be done programatically via the crawl manager API, but once I excluded those folders from the search scope, the indexing speed increased from 1-10 items per minute to about 1,000 items per minute.

    Was this answer helpful?

    1 person found this answer helpful.
  3. W104TP 1 Reputation point
    2026-03-09T22:13:13.68+00:00

    There is no option to expand Microsoft Outlook in the "Indexed Locations" window. There may have been in the past but there is no ">" to click to expand now.

    And none of the "BackOff" related changes make any difference. Again, they may have in the past but not now.

    Was this answer helpful?

    0 comments
  4. Harold E1 20 Reputation points
    2025-11-24T00:16:18.4966667+00:00

    In addition, I increased virtual maximum memory page size to 4926 from 2048.

    Was this answer helpful?

    0 comments
  5. Harold E1 20 Reputation points
    2025-11-18T05:01:49.6+00:00

    ​

    Is there any way to speed up Windows 11 file Explorer glacial file indexing? This article: https://learn.microsoft.com/en-us/answers/questions/2287023/windows-11-search-indexing-extremely-slow-on-fast says to uncheck the top-level item labeled "Public Folders". I did that and then the number of indexed files dropped by 20,000 or 30,000.

    ​This article​: https://office-watch.com/2022/force-windows-indexing-to-run-faster/​ says​ to​change a registry key called: HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows Search\Gathering Manager\DisableBackoff to a value of 1​. Unfortunately,​ when I tried that I wasn't able to.​ No was able to give myself the permissions​ that would've allowed me to do it​.​ Does anyone know​ a workaround around this?​

    This article​:​ https://windowsforum.com/threads/speed-up-windows-10-11-search-configure-indexing-options-rebuild-index.382226/​ says to eliminate certain file types from the indexing. It sounds like a great idea, but there must be 100's of file types and it would take forever to eliminate them 1 by 1. Is there some way to select a whole bunch of file types?

    Any other suggestions?

    Was this answer helpful?

Your answer

Answers can be marked as 'Accepted' by the question author and 'Recommended' by moderators, which helps users know the answer solved the author's problem.