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Hello Alex,
Thank you for your question and for reaching out with your question today.
Based on the information provided, there are a few potential areas to investigate and troubleshoot the issue with Outlook not starting correctly on the RDS (Remote Desktop Services) server. Here are some suggestions:
- DNS configuration:
- Verify that the DNS settings on the RDS server are correctly configured to resolve the autodiscover domain and other necessary records.
- Ensure that the autodiscover CNAME and other required DNS records (e.g., MX, SRV) are correctly set up for your custom domain.
- Certificate configuration:
- Check if the SSL certificate used for the autodiscover URL and other related services on the RDS server is valid and properly installed. Ensure it includes the correct subject alternative names (SANs) for your custom domain.
- Confirm that the certificate chain is complete and trusted by the RDS server and client machines accessing Outlook.
- Exchange and Active Directory configuration:
- Review the Exchange Server configuration for the autodiscover service, especially the virtual directories and autodiscover settings.
- Check the Active Directory user attributes for the affected users, such as the primary SMTP address, proxy addresses, and UPN (User Principal Name). Ensure they match the custom domain configured in Microsoft 365 and Exchange.
- Verify that the RDS server is correctly joined to the Active Directory domain and can access the necessary domain services.
- Outlook profile and authentication settings:
- If possible, test creating a new Outlook profile on the RDS server for an affected user and ensure the correct autodiscover settings are applied.
- Confirm that the Outlook clients on the RDS server are configured to use the correct authentication method (e.g., modern authentication) and that the necessary registry keys are set correctly.
- Logs and diagnostics:
- Enable logging for Outlook on the RDS server and review the log files to identify any specific error messages or warnings related to the issue.
- Monitor the event logs on the RDS server, Exchange Server, and Active Directory for any relevant events or errors occurring around the time of the Outlook startup issue.
- Microsoft Support:
- If the issue persists and you have an active Microsoft 365 subscription, consider reaching out to Microsoft Support for further assistance. They can provide more specific guidance based on your environment and access additional diagnostic tools.
Please note that the suggestions above are general recommendations, and it's important to thoroughly analyze and adapt them to your specific environment. It may also be beneficial to involve your IT team or a qualified consultant who can perform a detailed investigation of your setup and help identify the root cause of the Outlook startup issue on the RDS server.
I used AI provided by ChatGPT to formulate part of this response. I have verified that the information is accurate before sharing it with you.
If the reply was helpful, please don’t forget to upvote or accept as answer.