Microsoft 365 Copilot Shows Deleted SharePoint Content: Fix

You ask Copilot a question about a project file, and it returns results from a document you deleted from SharePoint last week. This problem causes confusion and trust issues with the AI assistant. The cause is a delay in how Microsoft 365 search indexes process deletion events from SharePoint and OneDrive. This article explains why Copilot can still see deleted content and provides the steps to force a re-index or remove the data permanently.

Why Copilot Returns Deleted SharePoint Content

Copilot uses the Microsoft Search index to find and retrieve content in Microsoft 365. When you delete a file from SharePoint, the deletion is recorded in the site, but the search index does not update instantly. The index refreshes on a schedule that can take up to 15 minutes for small sites and up to 24 hours for large tenant environments. During this window, Copilot can still query the stale index and return the deleted item as if it still exists.

The problem is more common in two scenarios:

First, when a user deletes a file and immediately asks Copilot a related question. The index has not processed the delete event yet. Second, when the SharePoint site uses a retention policy that places the deleted file in the Preservation Hold library. The file is hidden from users but still searchable by Copilot until the hold expires or the policy is modified.

The Role of the Search Index and Crawl Schedule

SharePoint search uses a crawl schedule to scan site content and update the index. Incremental crawls occur every few minutes, but full crawls happen only when triggered manually or during off-peak hours. If a file is deleted between two incremental crawls, the index still contains the old metadata. Copilot does not check the live site for existence before returning a result, so it relies entirely on the index state.

Retention Policies and Preservation Holds

A retention policy in Microsoft 365 Compliance can keep deleted content searchable for legal or compliance reasons. When a file is deleted, the system moves a copy to the Preservation Hold library within the site. This copy is not visible in the default document library, but it is still indexed. Copilot can find and return content from the Preservation Hold library as long as the policy is active. This is not a bug, but it behaves like one for users who expect deleted content to disappear from search immediately.

Steps to Remove Deleted Content from Copilot Results

Use these methods in order. Start with the simplest option and escalate if the problem persists.

Method 1: Force a Re-Index of the Site Collection

1. Sign in to SharePoint admin center
   Open a browser and go to https://admin.microsoft.com. Select SharePoint in the admin center navigation. If you do not see it, select Show all and then SharePoint.
2. Open the site collection settings
   In the SharePoint admin center, select Sites then Active sites. Find the site that contains the deleted content. Click the site name to open the details panel.
3. Navigate to Search settings
   In the details panel, scroll down and select Settings. Then select Search from the list.
4. Request a full re-index
   On the Search settings page, find the section labeled Re-index site. Select the checkbox that says Re-index site and then select Save. This triggers a full crawl of the entire site collection. Wait 15 to 30 minutes and then test Copilot again.

Method 2: Re-Index a Specific List or Library with PowerShell

1. Install and connect PnP PowerShell
   Open Windows PowerShell as administrator. Run Install-Module PnP.PowerShell -Scope CurrentUser. After installation, run Connect-PnPOnline -Url "https://yourtenant.sharepoint.com/sites/yoursite" -Interactive. Replace the URL with your actual site URL.
2. Identify the list or library that held the deleted content
   Run Get-PnPList -Identity "Documents" to confirm the list exists. Replace Documents with the name of your library.
3. Request a re-index of the list
   Run Request-PnPReIndexList -Identity "Documents". This command forces a full re-index of that specific list or library. Wait 10 to 20 minutes and then test Copilot.

Method 3: Check and Modify Retention Policies

1. Open Microsoft 365 Compliance center
   Go to https://compliance.microsoft.com and sign in with an account that has Compliance Administrator or Global Administrator role.
2. Go to Data Lifecycle Management
   In the left navigation, select Data lifecycle management then Retention policies. Review the list of policies that apply to SharePoint sites.
3. Find the policy that applies to the site
   Select a policy and review the Locations section. If the policy includes the site where the deleted content resides, it may be preserving the content.
4. Adjust the retention action
   If the policy is set to Keep content for a period, you can change the action to Delete content automatically after the retention period ends. Select Edit policy, go to the Actions step, and set Delete items automatically. Save the policy. This does not remove content already in the Preservation Hold library, but it prevents future content from being preserved.
5. Manually delete content from Preservation Hold library
   To remove content already preserved, go to the SharePoint site. Select Site contents in the left navigation. Look for Preservation Hold Library. If you see it, open it and delete the files. You need site collection administrator permissions to see this library.

Method 4: Clear the Browser Cache and Reset Copilot Session

1. Clear browser cache for Microsoft 365
   In Chrome, select the three-dot menu then Settings > Privacy and security > Clear browsing data. Set time range to All time. Check Cached images and files. Clear the data.
2. Sign out of Microsoft 365 and sign back in
   In any Microsoft 365 app, select your profile picture in the top right corner and select Sign out. Close the browser. Open a new browser window and sign in again.
3. Close and reopen the Copilot pane
   In Word, Excel, or PowerPoint, select the Copilot icon in the ribbon. The pane opens. Select the three-dot menu in the pane and select Refresh. This resets the session state.

If Copilot Still Shows Deleted Content After the Main Fix

Deleted Files Appear in Copilot Chat History

Copilot stores chat history in the user’s Exchange Online mailbox. If you referenced a deleted file in a previous conversation, Copilot may show a reference to that file in the chat history. The file itself is gone, but the reference remains. To clear this, delete the chat conversation. In the Copilot pane, select the chat history icon. Find the conversation, select the three-dot menu, and choose Delete.

Copilot Returns Results from a Different Site

If Copilot returns content from a site that you did not expect, the search index may be returning results from a different site collection. Verify that the file you think is deleted actually resides on the site you re-indexed. Use the SharePoint admin center to search for the file by name. If it still exists on another site, delete it from that site as well.

Third-Party Backup or Sync Tools Restore Deleted Content

Some organizations use third-party backup tools that restore deleted SharePoint files automatically. If a backup tool restores a file after you delete it, Copilot will see the restored version. Check the audit log in the Microsoft 365 Compliance center. Search for events where the file was restored. If you find a restore event, contact your backup administrator to stop the restore process for that file.

Item	Method	Result
Description	Force site re-index	Removes deleted content from search index within 30 minutes
Speed	15 to 30 minutes	Fastest option for immediate fix
Permissions needed	SharePoint admin	Site collection administrator or higher
Scope	Entire site collection	Affects all lists and libraries on the site

After you force a re-index or adjust retention policies, Copilot should stop returning the deleted content within one hour. Test by asking Copilot a question that previously returned the deleted file. If the file still appears, repeat the re-index step and verify that no retention policy is preserving the content.