Copilot Cowork skills not working

Jayakumar Janardhanan (TCS) 40 Reputation points
2026-08-17T03:53:59.33+00:00

Copilot Cowork skills not working. Skills not being invoked, installs corrupted

Microsoft Copilot | Windows Copilot | Feature
0 comments

2 answers

Sort by: Most helpful
Most helpful Newest Oldest
  1. Vikki-T 9,685 Reputation points Microsoft External Staff Moderator
    2026-08-20T06:50:32.2+00:00

    Hi Jayakumar Janardhanan (TCS),

    I understand how disruptive it can be when Cowork skills appear to install but are not invoked as expected.

    At this point, I recommend that you review and try the steps provided in the AI generated answer on your thread. That reply typically include the most relevant checks for this scenario. 

    To help narrow this down, could you clarify a few details?

    • Is this happening with a built-in skill, a custom skill or a plugin-based skill?
    • Does the affected skill still appear in the available skills list, or has it disappeared completely?
    • When you say the installation is “corrupted,” do you receive a specific error message?
    • Does this affect all skills or only one particular skill, including in a new Cowork conversation?

    If possible, please share the exact error message or a screenshot with any personal or organizational information removed. This will help determine whether the behavior is related to the individual skill, its installation, or the organizational environment. Thank you so much for your understanding. 

    Note: Please follow the steps in our documentation to enable e-mail notifications if you want to receive the related email notification for this thread.

    Was this answer helpful?

  2. AI answer

    2026-08-17T03:54:18.2+00:00

    For Copilot Cowork skills not being invoked or appearing corrupted, use this end-to-end check:

    1. Restart the Cowork session If skills or plugins were just added, removed, or updated, restart the session. Removed plugins are only removed from the next session, and stale plugin versions can remain active until restart.
    2. Verify the plugin is installed and enabled In Cowork:
      • Open a conversation or the Cowork home page.
      • Select + > Customize.
      • Confirm the expected plugin is present.
      • Open Sources & Skills and make sure the plugin is toggled on.
      When enabled, plugin skills should appear alongside built-in skills.
    3. Reacquire or reinstall the plugin If the install appears corrupted, remove the plugin and add it again from the Microsoft 365 plugin marketplace. After removal, its skills and connectors are removed from the next session, so start a new session after reinstalling.
    4. Check whether the plugin is blocked by admin policy If the plugin does not appear at all, it might require organizational approval. Check with the IT admin because some plugins must be approved before they show in the list.
    5. Confirm the prompt is specific enough Cowork invokes skills based on the request. Built-in and plugin skills are acquired dynamically as needed during a conversation, so vague prompts might not trigger the intended skill. Use a prompt that clearly names the task or domain the skill supports.
    6. If using custom skills, verify the skill files and limits Custom skills are stored in OneDrive under: Documents/Cowork/skills/{name}/SKILL.md Supported limits:
      • Up to 50 custom skills
      • Up to 20 companion files per skill
      • 5 MB per companion file
      • 10 MB total per skill
      Cowork discovers custom skills automatically at the start of each conversation, so after fixing a custom skill, start a new conversation.
    7. Check for Information Barriers restrictions If the tenant has Microsoft Purview Information Barriers enabled, plugin or skill management and sharing are not currently supported, and embedded knowledge file uploads are blocked. That can prevent affected plugins or skills from being uploaded or published.
    8. If the issue is in Dynamics 365 Sales Copilot scenarios If the failing skill is tied to Dynamics 365 Sales, check these two causes:
      • Republish the Copilot in Dynamics 365 Sales agent if initial publishing failed.
      • In Power Platform admin center > Data policies > Data loss prevention, unblock and group these connectors together in the same policy:
        • Microsoft Dataverse
        • Direct Line channels in Copilot Studio

    If the symptom is specifically that skills install but never trigger, the most likely checks are: plugin enabled in Sources & Skills, new session started, plugin approved by admin, and prompt specific enough to invoke the skill.

    AI-generated content may be incorrect. Read our transparency notes for more information.

    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.