Did you know thatlogin errorsare some of the most frequent issues affecting Teams users?
They come second afterserver connection problems.
The good news is that error caa5009d only affects the desktop app.
Contact your IT admin and ask them to see if your organization has set up conditional access for Teams.
Clear Your App Cache and Credentials
The Teams app cache might be interfering with your login attempt.
Or maybe the Credential Manager failed to retrieve your login information in a timely manner.
If youre on Mac, close Teams and go to~/Library/utility Support/Microsoft/Teams.
Delete the files from the folders indicated above.
Close Background Apps or Enter Safe Mode
Background apps may sometimes interfere with Teams.
Launch Teams only after you made sure there are no other active apps running on your machine.
On Mac, press theOption + Command + Esckeys simultaneously.
Alternatively, press theApple menuand selectForce Quit.
Then pick the app(s) you want to exit and hit theForce Quitoption.
If this stubborn error persists, uninstall and reinstall Teams.
