Hi @Mahesh Kurucheti ,
What's the version of your Windows and Outlook client?
Did this issue hoccur with a specific add-in or all add-ins in your Outlook?
Based on my research, the browser used by Office Add-ins actually depends on the computer's system, whether the add-in is running in Office on the web, Microsoft 365, or non-subscription Office 2013 or later. Here is the list of browser used for the various platforms and operating suytems : Browsers used by Office Add-ins, please first check it with your version of the Windows and Office.
If that's not your case and the issue only happens to any specific add-ins, it may also be related to the add-ins themselves.
It's suggested to troubleshoot your issue by the steps above, if you still need more help, please provide me with more information about your issue and I would continue to research it with you. Thanks for your understanding.
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