01Type '/' to reference OneDrive or SharePoint filesVerified
Typing '/' in the Copilot Chat prompt box opens the ContextIQ menu, where you search for a file you have access to. The file is added to the prompt as if you had uploaded it.
- Type '/' in the Copilot Chat prompt box
- Type part of the file name and pick it from the list (people, meetings, and emails can also be referenced)
- Write your instruction and send
- Check that the citations point to the file you chose
Using /approved product information summary.docx, draft answers to five frequently asked questions from healthcare professionals (within the approved scope), and cite the relevant sections.
Referencing the master file with '/' avoids version drift compared with uploading a local copy. Per July 2026 release notes, SharePoint Lists can also be selected in the ContextIQ menu (Web). Put draft answers through your internal review before use.
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Users type '/' in the prompt box to open the ContextIQ menu and search for a specific file they have access to. This adds the file to the prompt for Copilot Chat to reason over, just as if they had uploaded the file.
02Uploaded files are stored in your OneDriveVerified
Files uploaded with the + button or drag and drop in Copilot Chat are stored in your OneDrive for Business as part of enterprise data protection. PowerPoint files generated by Copilot Chat are also stored in your OneDrive if storage is available.
- Select + in the chat box or drag and drop a file into it
- For documents with a master copy, reference the original with '/' instead of uploading
- Periodically check your OneDrive for files created by uploads or generation
- Handle copies you no longer need according to your company's retention and disposal rules
An uploaded copy is a separate file and does not update when the original is revised. Watch the sharing settings of copies in your OneDrive.
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Users upload a file by selecting the '+' button in the chat box. They can also drag and drop a file into the chat box. Uploaded files are stored in a user's OneDrive for Business as part of enterprise data protection.
03How your license changes OneDrive and SharePoint accessVerified
With a Microsoft Copilot license, Work IQ and semantic indexing give access to the full work data you can reach. Without it, Copilot Chat in Outlook can use only a limited set of files, such as your OneDrive and recently used files.
- Confirm your license with your admin
- Without a license, name files explicitly with '/' or upload
- Copilot Chat in Outlook uses your OneDrive files, frequently visited SharePoint sites, files shared directly with you, and files you viewed, edited, or created
- With a license, turn on Work IQ to search across your work data
Without a license, Copilot Chat in Outlook uses lexical indexing, so reworded terms may not match. Not finding a document does not mean it does not exist.
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User data used by Copilot Chat in its response is accessed via lexical indexing. Access to full work data as part of Work IQ and semantic indexing is only available for users with the Microsoft Copilot license.
04Scope Copilot to a SharePoint library or folderVerified
When you attach a SharePoint document library or folder, or provide its URL, Copilot limits grounding to that scope and uses the library's column metadata to refine and rank results.
- Copy the URL of the document library or folder
- Paste the URL into your prompt or attach the library or folder
- Ask using column values (version, effective date, document type, and so on)
- Keep column values accurate in the library
In (SOP library URL), find the SOPs with document type 'release decision' and the most recent effective date, and list their versions and effective dates.
This works in the web experience, and the site or library must remain searchable. Empty or wrong column values reduce accuracy.
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When a user attaches a SharePoint document library or folder (or provides its URL) in Copilot, Copilot can use the library's column metadata as additional signals to refine grounding, improve contextual relevance, and increase answer accuracy.
05Copilot in OneDrive: supported types and 150 MB limitVerified
Copilot in OneDrive supports Office documents, Loop, PDF, text, web files, and OpenDocument formats. Files must be under 150 MB. Images, meeting recordings, videos, and OneNote notebooks are listed as coming soon.
- Check that the file type is on the supported list
- Split PDFs and other files of 150 MB or more
- Image-only scans may not be supported; use formats that contain text
Supported formats and limits may change. This limit is from the Copilot in OneDrive FAQ and is separate from limits in other experiences such as Copilot Chat.
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Office documents: DOC, DOCX, PPT, PPTX, XLSX
06Your sharing settings define what Copilot can surfaceVerified
Copilot in OneDrive can only access files you have permissions for, including files in your OneDrive and files shared with you. Conversely, broadly shared files become easier for others to find through their Copilot.
- Share drafts with 'Specific people' links
- Periodically review files shared with 'People in the organization' links
- Remove sharing you no longer need
- Apply sensitivity labels to highly confidential files
Per the semantic index documentation, sharing with an organization-wide link does not add a file to the tenant-level index; it is added to the user index of people who open the link. The SharePoint Advanced Management page notes that SharePoint's default sharing setting is the most permissive option. Follow your company's sharing rules.
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Copilot can only access files that you have permissions for. This includes files in your OneDrive as well as files shared with you in your organization.