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Outlook | Windows | Classic Outlook for Windows | For business
Using classic Outlook for Windows in business environments
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Hi @Pragati Singh ,
Regarding the registry deletion you mentioned, which one is it specifically?
Based on my searches, this could be an issue with the mailbox properties not properly referencing hidden messages in the mailbox. In this case, we recommend that you follow the steps provided in this link: You experience issues in Outlook when you try to configure free/busy information or when you try to delegate information
In addition, if your mailbox is migrated from a local Exchange environment to Microsoft Exchange Online, you may also encounter this issue, please refer to this article: Error viewing delegates in Outlook after a migration from on-premises to Exchange Online
Hope above can help you!
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