Hi @AbzSabz ,
Did this issue occur on all users in your organization? In order to further confirm if your issue is related to your client or mailbox, please log in to your web mail to check if the issue could be reproduced there.
If the issue occurred on Outlook only, in the point of messages, did it occurred on any specific messages or all messages? And where are they stored (in your mailbox or in the local .pst file)? Could you open it normally from your folder directly instead of after searching it?
- If the messages are stored in your mailbox, I understand that you are working with exchange account, is it right? If so and if you are working with cached exchange mode, please try to uncheck this option and work in online mode to check if the issue has any difference(File>Account settings>Account settings>uncheck use cached exchange mode).
- If it could work normally in online mode, the issue may be related to your local data file(.ost), it's recommended to rename the local data file and restart your Outlook with cached exchange mode to check(File location: C:\Users\Username\AppData\Local\Microsoft\Outlook).
- If the issue still exists or you even couldn't work in online mode, considering corrupted outlook profile may also cause it, please try to receate a new Outlook profile and readd your account to check(Control panel>Mail>show profiles>add>type the profile name>readd your account)
If your issue has any update, please feel free to post back.
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