Copilot Studio agent not working in Teams: SystemError and fixes

Published, but silent, "You don't have access to talk to this bot" or SystemError in Teams? Fix sharing, Teams app settings, stale versions and group chats.

Copilot StudioFix a problem11 min read

Checked against Microsoft Learn 27 Oct 2026 · 9 sourcesPosted by the Maker DeskHow we write guides

The agent answers perfectly in the Copilot Studio test pane. You publish it, open it in Teams, and nothing happens. Or it replies with an error, or with last week's answers, or it works for you and not for your colleagues. When a Copilot Studio agent is not working in Teams, check what sits between "published" and "answering in Teams": sharing, a Teams app setting, an old version Teams is holding on to, or a limit of group chats. This guide takes each one in turn, with the fix Microsoft documents.

What are you seeing?

access The agent says you don't have access to talk to itit's installable but not shared with you, or Teams blocks it.
blocked Installing it says your organization has prevented itan admin setting or policy stops the install.
silent It works in Copilot Studio and says nothing in Teamsa Teams app setting, or a missing identity.
old Your changes don't show upthe conversation, or Teams itself, still has the earlier version.
SystemError Teams shows "Sorry, something unexpected happened" after you republish.
group It answers one-to-one but not in a channel.

From "published" to "answering in Teams"

Step 1Published at least once
Step 2Shared with the person chatting
Step 3Allowed in the Teams admin center
Step 4One-to-one chat, or a group chat without sign-in knowledge
Step 5Latest version, after Start over or a refresh
Step 6The agent answers in Teams

Match your symptom to the cause

What you see	Most likely cause	Go to
"You don't have access to talk to this bot, contact the owner."	The agent can be installed but isn't authorised for this person	Installed, but it won't chat
"Your organization has prevented this agent from being installed."	An agent setting or a Teams app policy blocks the install	It can't be installed
No reply in Teams, although the test pane works	A Teams setting for custom apps, or the agent's Entra app registration is missing	It answers in Copilot Studio but not in Teams
Old answers, old name or old icon	The conversation or Teams is using an earlier version	It gives old answers after you publish
"Sorry, something unexpected happened. We're looking into it." with Error code SystemError	Teams kept a previously published version	SystemError
Works one-to-one, fails in a channel or group chat	Sign-in knowledge such as SharePoint, or manual authentication with Teams SSO	Group chats
Works for you, fails for colleagues	Flows, connections or the model aren't available to them	It works for you but not for others

Before any of these, check two basics. The agent must be published at least once before anyone can use it in Teams. And for publishing through the built-in Teams + Microsoft 365 channel (the Teams and Microsoft Copilot channel on the Channels page), Microsoft says to use Authenticate with Microsoft in the agent's authentication settings (Settings, then Security, then Authentication). Authentication changes only take effect after you publish again.

Installed, but it won't chat

Microsoft's known-issues page describes this exact case: people find and install the agent, then every prompt gets "You don't have access to talk to this bot, contact the owner." and nothing else. The agent is installable, but tenant app settings or the agent's sharing haven't given that person access. Microsoft's resolution has four parts:

Allow custom apps in Teams. A Teams admin, in the Teams admin center, goes to Teams apps > Manage apps > Actions > Org-wide app settings. Under Custom apps, they turn on Let users install and use available apps by default and Let users interact with custom apps in preview.
Allow the Shared Power Apps app. On the same Manage apps page, the admin allows Shared Power Apps. That Microsoft app is how content shared from Power Platform, including Copilot Studio agents under Built with Power Platform, reaches Teams.
Share the agent with the person. In Copilot Studio, open the agent, select the three dots (…) on the top menu bar, then Share. Add a security group, or choose everyone in your organization with User - can use the agent. Microsoft notes that someone can install or reach an agent in Teams and still not chat with it until it's shared with them or a group they're in.
Share any connected agent too. If your agent calls another agent, people need permission on that one as well.

Retest with the affected person's account, not yours. Owners and collaborators always have access, so your own test proves nothing about theirs.

Tip

If you share with a security group, check the person is in that exact group. People chatting also need the ChatBotReaders privilege in the agent's environment; the Environment Maker role includes it, and a System Administrator can assign that role while sharing.

It can't be installed

"Your organization has prevented this agent from being installed." means the agent was shared, but an admin setting stops the install. Microsoft lists the checks for a Microsoft 365 admin:

In the Microsoft 365 admin center, Agents > Settings > Agent and plugin access: Allow agents and plugins built by your organization is on.
In the same place, User access: agents are available to everyone, or to a user or group that includes this person.
In the Teams admin center, Teams apps > Manage apps > Org-wide app settings: custom apps are allowed. The app permission and app setup policies assigned to the person don't block the agent.
The person belongs to the exact security group the agent is shared with.

It answers in Copilot Studio but not in Teams

Microsoft documents two causes for an agent that's silent in Teams:

Teams blocks interaction with custom apps. In the Teams admin center, Teams apps > Manage apps > Actions > Org-wide app settings, set Let users interact with custom apps in preview to On. This setting governs agents shared by an installation link and agents in Built with Power Platform. Once an admin has approved the agent into the organization's catalog (Built for your org), the setting no longer applies; app permission policies and the app's status on Manage apps do.
The agent's Microsoft Entra app registration is missing. That registration is the agent's identity. In Copilot Studio, go to Channels, disconnect the Teams channel, wait one to two minutes, reconnect it, and publish again. Republishing should recreate the missing registration. If it doesn't, Microsoft's fallback is to create a new agent, move the topics and configuration across, and publish that instead.

It gives old answers after you publish

New content in a freshly published agent doesn't reach conversations already under way. Type Start over in the chat to begin a new conversation with the latest version.

Other changes take longer:

Teams caches app details. If the agent doesn't appear in Built with Power Platform, or an approved agent doesn't appear in Built for your org, sign out of the Teams desktop app and back in, or refresh the browser for Teams on the web.
New details need a reinstall. People who installed the agent from a shared link or from Built with Power Platform don't see a new icon, colour or description until they reinstall it.
Approved agents need resubmitting for details only. For an agent an admin approved, a change to its details needs a new approval. Content changes don't: you can publish them as often as you like, and approved users get them.

Sorry, something unexpected happened: SystemError

After you publish or republish, people in Teams may see:

text

Sorry, something unexpected happened. We're looking into it.
Error code: SystemError

Microsoft explains that Teams can keep using the previously published version of the agent and not pick up the new configuration straight away. Its workaround, in order:

In the Microsoft Teams admin center, find the agent's app, disable it, wait a few seconds, and enable it again.
In Copilot Studio, turn the agent's Teams channel off, save, and turn it back on.
Republish the agent.

If the error continues, contact Microsoft Support with the conversation ID, the agent ID and the time the error happened. Note them down when it happens, before you start changing things.

It works one-to-one but not in a group chat

Agents in Teams group chats and channels have documented limits:

They can't use knowledge that needs the person's own sign-in, such as SharePoint. Microsoft says this is by design, to help prevent unintended data exposure. Those agents work in one-to-one chats only. Our knowledge limits guide lists the sign-in rule for each source.
Group chats and meeting chats don't support manual authentication with single sign-on for Teams. Use Authenticate with Microsoft, or remove Teams SSO from the manual authentication.

If you let people add the agent to a team, set it so everyone in your organization can chat with it, and don't change that security setting afterwards. Otherwise team members can get permission errors in channels and group chats. Teams caches here too, so the option to add the agent to a team can take a while to appear.

It works for you but not for others

When only the maker gets answers, look at what the agent depends on:

Flows aren't shared with the agent. Sharing an agent doesn't share the Power Automate flows it calls. Make sure the people chatting have the permissions the flows need; the test pane runs them for you, so it can hide the gap.
Connections belong to each person. A connection to an external service is tied to the identity of the person chatting, which is why an agent can work for you and not for others. Microsoft suggests a service principal, environment-level connections, or asking each person to sign in.
A third-party model. If the agent uses a third-party model that an admin must enable, people without access get an "Agent Blocked" error. An admin grants access in the Microsoft 365 admin center, or you switch the agent back to the default Microsoft model.
Access narrowed after approval. After you submit an agent for admin approval, don't reduce its access below everyone in the organization. People who install it from the store then can't chat with it.

In Microsoft Copilot, not in Teams

The same channel can also make the agent available in Microsoft Copilot, which has its own limits. It doesn't support the Conversation Start topic, so there's no greeting; the agent offers suggested prompts instead. Basic cards, video and images fail with a ContentFiltered error (Adaptive Cards can show images). File messages aren't supported, GIF images aren't rendered, and Microsoft Copilot may remove embedded links for security. If the agent works in Teams but not there, check these before anything else.

Publish once, install the agent for yourself in Teams, then share it.
Test with a colleague's account in a one-to-one chat before adding the agent to a team.
Type Start over after every publish you want to check.
Write down the conversation ID, agent ID and time when an error appears.

Don't

Don't assume "installed" means "allowed to chat": sharing and the Teams settings are separate.
Don't count on SharePoint knowledge in channels or group chats.
Don't narrow an approved agent's access below everyone in the organization.

For the first build and a small-group launch, see your first Copilot Studio agent.