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This mail does not update visually after the action is done.
What do you mean about "update visually"? Is that after reading an email, the email remains unread? Or something else?
According to your description, i notice that the issue occurs in one specific user, in order to further confirm the issue is related to the user's Outlook desktop client, please configure the user's account in other users' computer to check if there're any differences.
If everything is ok in other users' computer, please try the following troubleshooting steps in the specific user's Outlook:
- Considering the impact of some add ins, It is suggested that you try to start outlook in safe mode(win+R>type: outlook /safe) to check whether it works normally.
- If this is still the issue in safe mode, it is suggested that you could try to create a new profile(Control Panel>Mail>Show Profiles>add) and add the account for testing to check if there are some differences.
If the above doesn't help, please provide more information as i mentioned in the beginning.
If the answer is helpful, please click "Accept Answer" and kindly upvote it. If you have extra questions about this answer, please click "Comment".
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