It sounds like you are experiencing authentication issues with your Outlook app on your Android device. Here are a few troubleshooting steps that might help resolve the issue:
- Check for TLS Version: Ensure that your Exchange server is using TLS 1.2 or later, as Outlook for Android does not support TLS 1.0 or 1.1. If your server is using an older version, you may need to update it.
- Check AutoDiscover Endpoint: If the AutoDiscover endpoint cannot be reached, it could be due to firewall or load balancer configuration issues. Make sure that there are no IP restrictions preventing access.
- Verify ActiveSync Configuration: Ensure that the ActiveSync endpoint is correctly configured and reachable. If there are issues with the ActiveSync endpoint, it may prevent authentication.
- Check for Certificate Issues: If your operating system uses TLS 1.2 but you still face issues, check if there is an expired TLS certificate that might be causing the problem.
- Use Hybrid Modern Authentication: If your organization supports it, consider deploying Hybrid Modern Authentication, which can enhance security and may help with authentication issues.
If these steps do not resolve the issue, you may want to consult additional resources or reach out to your IT support for further assistance.
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