Teams chat issue

It seems that user A is experiencing a specific issue when trying to send messages to user B in Microsoft Teams. Here are some potential reasons and solutions:

1. User Status: Ensure that user B is not set to an inactive status (like Offline or Do Not Disturb) in Teams, as this could prevent messages from being delivered.
2. Compatibility: Since user A can send messages to all other users and the issue is specific to user B, verify that both users are using compatible versions of Teams. If user B is on a different platform or version, it may affect message delivery.
3. Teams Cache: Although you mentioned clearing the Teams cache files, it might be worth trying again or checking for any updates to the Teams application that could resolve bugs related to messaging.
4. Mobile Functionality: Since messaging works on mobile for user A, it may indicate that the issue is specific to the desktop application. Consider reinstalling the desktop app or checking for any updates.
5. Network Issues: Sometimes, network connectivity issues can cause messages to not send properly. Ensure both users have stable internet connections.

If the problem persists, it may be beneficial to reach out to Microsoft support for further assistance.

References:

• Microsoft Teams user cannot send a message in Skype for Business

Hello @Gary Gu-ext,  

Good day! Thank you for posting your valuable question on Microsoft Q&A forum.   

To ensure I provide the most accurate and helpful solution, I’d appreciate a bit more information about the situation: 

• Are Users A and B signed into Teams with personal accounts (e.g., Hotmail, Gmail, Yahoo, Outlook.com) or work/school accounts (e.g., accounts associated with your organization’s domain)? 
• If they’re using work/school accounts, are they part of the same organization or different ones? 
• If User A signs in on another device, does the issue still occur when messaging User B? 
• Has User A tried using other Teams platforms (e.g., desktop app, web version)? If so, does the issue persist across all platforms? 
• Is User A the only one experiencing this issue with User B, or are other users also unable to message User B? 
• What operating systems are both users currently using (e.g., Windows, macOS, iOS, Android)? 
• Could you share how the Teams cache was cleared (e.g., manually deleting files, using a script, or another method)? 

This additional context will help us better understand your environment and the steps already taken, so we can tailor our guidance accordingly. 

I apologize for not jumping straight to a solution. I want to avoid suggesting anything that might be inaccurate or unhelpful. Once I have the details above, I’ll be able to assist you more effectively and guide you toward the right resolution. 

Looking forward to your response so we can get this sorted out for you as soon as possible. 

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@Tamara-Hu Thanks for your suggestion. Now I want to try remove A and B teams from win11/win10, so could you pls tell me after uninstall teams from control panel then how to empty the teams cache folders.

Hello @Gary Gu-ext,    

Thank you for your follow-up. To completely remove Microsoft Teams and clear all cached data after uninstalling, please follow these steps: 

Clear Teams Cache  

On Windows:   

• Navigate to your Taskbar and look for the Microsoft Teams icon. Right-click the icon and choose Quit. This will force the Teams app to quit.   
• Next, copy and paste the following location into File Explorer: %appdata%\Microsoft\Teams, and delete the contents of the entire folder.   
• Restart Microsoft Teams by opening the application and logging back in.    

Note: Deleting the cache won't remove Microsoft Teams from your device, but will remove the web client cache, icons, thumbnails, local message history, your Teams display images, and any other Teams add-ons.  

I also recommend you to Clear Credential Cache: 

• Press Win + S, type Credential Manager, and open it. 
• Go to Windows Credentials. 
• Look for entries related to:  
  • MicrosoftOffice16_Data:ADAL 
  • MicrosoftOffice16_Data:SSO 
  • Anything with Teams or Office. 
• Click Remove for those entries. 
• Optional: In Credential Manager, also check Web Credentials for Microsoft-related entries and remove them. 

Please let me know if these steps work for your issue. Thank you for your time and effort.

Thanks for your help, I will follow up these steps .