How do I make sure that Teams are sending all my messages?

Hello @Hans Ljungberg,

Thank you for posting your question in the Microsoft Q&A Forum. 

Before we proceed, could you confirm whether all messages fail to send when this happens, or only some messages?  
If all messages are failing to send, please start by checking your internet connection. Make sure it’s stable, and if you’re using a VPN, try disabling it temporarily. If possible, switch to a wired connection for better reliability. 

Next, please try signing in to Teams Web at https://teams.microsoft.com. If messages send successfully there, the issue is likely with the desktop app rather than your account or network. 

If the problem seems to be with the desktop app, here are a few steps you can try: 

1. Clear the Teams Cache 

Instead of just logging out, I recommend you perform a full cache clear. This is a more permanent solution.  
The steps are different depending on which version of Teams you use. You can follow this article for detailed instruction: Clear the Teams client cache - Microsoft Teams | Microsoft Learn 

2. Clear Old Credentials 

In some cases, clearing outdated credentials in Windows Credential Manager can resolve authentication conflicts. 
Go to "Credential Manager" > "Windows Credentials" > remove any entries related to MicrosoftTeams, msteams, live.com, or office.com, then restart Teams. 

One simple tip you can also try: Always close Teams through the system tray rather than just clicking the X button, as Teams continues running in the background and may prevent proper cache clearing. 

Please try these steps and update me on the outcome. Your feedback will help us determine the next steps and provide the best possible solution. 

I hope this helps, and I look forward to hearing back from you. 

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