cannot open microsoft outlook. cannot open folder group

Question

we work with terminal server. some times , the users cant open outlook and they get the known error :

cannot start microsoft outlook. cannot open the outlook windows. the set of folders cannot be opened. the attempt to log on to microsoft exchange has failed.

i have to delete the users mail profile and build a new one. cant microsoft solve this ? it is very annoying . anyone have a solution ?

Answer 1

The error message you are encountering, "Cannot start Microsoft Outlook. Cannot open the Outlook window. The set of folders cannot be opened. The attempt to log on to Microsoft Exchange has failed," can be caused by several issues. Here are some potential solutions:

1. Check Network Connectivity: Ensure that the terminal server has a stable connection to the network and that the Microsoft Exchange Server is accessible.
2. Update Outlook Profile: If users frequently encounter this issue, it might be beneficial to update their Outlook profiles to ensure they are configured correctly. This can be done by going to Control Panel > Mail > Show Profiles and creating a new profile.
3. RPC Encryption Requirement: If you are using a mailbox on a server running Microsoft Exchange, ensure that RPC encryption is enabled in the Outlook profile settings. This can help resolve connection issues.
4. Check for Compatibility Mode: Make sure Outlook is not running in compatibility mode for a different operating system, as this can lead to startup issues.
5. Review Shared Mailboxes: If users have many shared folders or mailboxes open, it may affect performance and connectivity. Reducing the number of open shared items can help.

If these steps do not resolve the issue, it may be necessary to continue deleting and recreating the mail profile as a temporary workaround. However, it is advisable to report this issue to Microsoft support for further assistance and potential long-term solutions.

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References:

• Outlook connection issues with Exchange mailboxes caused by the RPC encryption requirement
• You cannot start Outlook in cached mode or create a new cached mode profile

Answer 2

Dear @Adi,

Welcome to Microsoft Q&A Forum! 

Thank you for reaching out regarding the issue you're experiencing with starting Outlook. Based on the error message, it appears that Outlook is unable to open due to a problem connecting to Microsoft Exchange or accessing your folders. 

Therefore, I have done my best to research and found that Microsoft provides a detailed support article with several troubleshooting methods. You can access it here: I can’t start Microsoft Outlook or receive the error “Cannot start Microsoft Outlook. Cannot open t… 

Here are a few key steps from the article you may try: 

1.Start Outlook in safe mode and disable add-ins. 

2.Create a new Outlook profile. 

3.Repair your Outlook data files.

4.Recover the Navigation Pane configuration file by running the /resetnavpane command. 

5.Please make sure that Office and Windows are up to date. 

Besides that, if these steps above do not work, please follow this article that may be related to your case: [Solved] Cannot start Microsoft Outlook. Cannot open the Outlook window. The set of folders cannot …

Note: Please note that our support is limited to providing guidance based on official Microsoft documentation. Any third-party resources or references shared are intended solely for informational or consultative purposes. Microsoft does not guarantee the accuracy, reliability, or continued availability of third-party content, and we recommend exercising discretion when referring to such materials. 

I hope this information can help you to solve this issue and please feel free to let me know your feedback in comment section. Wish you a pleasant day! 

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