Microsoft Teams 'couldn't connect' error affects desktop and web apps
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Microsoft Teams users are experiencing 'couldn't connect' errors when launching the desktop and web applications. The issue is due to a recent change in the Teams sidebar, which introduced an unoptimized code flow. The problem is being addressed with a fix that is currently rolling out. Affected users see an error message stating 'We couldn't connect to this app.' The issue impacts users attempting to launch the Microsoft Teams desktop and web apps. Microsoft has provided a temporary workaround to bypass the error message by clicking the 'Activity' or 'Chat' buttons. The fix is expected to be fully deployed by the end of the week.
Timeline
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19.08.2025 21:07 📰 1 articles · ⏱ 28d ago
Microsoft Teams 'couldn't connect' error affects desktop and web apps
Microsoft Teams users are experiencing 'couldn't connect' errors when launching the desktop and web applications. The issue is due to a recent change in the Teams sidebar, which introduced an unoptimized code flow. A fix is being rolled out and has reached 25% of affected customers. The fix is expected to be fully deployed by the end of the week. A temporary workaround involves clicking the 'Activity' or 'Chat' buttons to bypass the error.
Show sources
- Microsoft shares workaround for Teams "couldn't connect" error — www.bleepingcomputer.com — 19.08.2025 21:07
Information Snippets
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The 'couldn't connect' error in Microsoft Teams is caused by a recent change to the sidebar.
First reported: 19.08.2025 21:07📰 1 source, 1 articleShow sources
- Microsoft shares workaround for Teams "couldn't connect" error — www.bleepingcomputer.com — 19.08.2025 21:07
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The error message displayed is 'We couldn't connect to this app.'
First reported: 19.08.2025 21:07📰 1 source, 1 articleShow sources
- Microsoft shares workaround for Teams "couldn't connect" error — www.bleepingcomputer.com — 19.08.2025 21:07
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The issue is tagged as an advisory, suggesting it may be limited in scope or intermittent.
First reported: 19.08.2025 21:07📰 1 source, 1 articleShow sources
- Microsoft shares workaround for Teams "couldn't connect" error — www.bleepingcomputer.com — 19.08.2025 21:07
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A fix is being rolled out and has reached 25% of affected customers.
First reported: 19.08.2025 21:07📰 1 source, 1 articleShow sources
- Microsoft shares workaround for Teams "couldn't connect" error — www.bleepingcomputer.com — 19.08.2025 21:07
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The fix is expected to be fully deployed by Thursday.
First reported: 19.08.2025 21:07📰 1 source, 1 articleShow sources
- Microsoft shares workaround for Teams "couldn't connect" error — www.bleepingcomputer.com — 19.08.2025 21:07
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A temporary workaround involves clicking the 'Activity' or 'Chat' buttons to bypass the error.
First reported: 19.08.2025 21:07📰 1 source, 1 articleShow sources
- Microsoft shares workaround for Teams "couldn't connect" error — www.bleepingcomputer.com — 19.08.2025 21:07
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Microsoft has previously mitigated a Teams outage in March that affected auto-attendant and call queues.
First reported: 19.08.2025 21:07📰 1 source, 1 articleShow sources
- Microsoft shares workaround for Teams "couldn't connect" error — www.bleepingcomputer.com — 19.08.2025 21:07
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Microsoft is enhancing protection against malicious URLs and dangerous file types in Teams chats and channels.
First reported: 19.08.2025 21:07📰 1 source, 1 articleShow sources
- Microsoft shares workaround for Teams "couldn't connect" error — www.bleepingcomputer.com — 19.08.2025 21:07
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An allow/block list feature is being added to help security administrators block communications from blocked domains.
First reported: 19.08.2025 21:07📰 1 source, 1 articleShow sources
- Microsoft shares workaround for Teams "couldn't connect" error — www.bleepingcomputer.com — 19.08.2025 21:07
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