Hi @Anand
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For better research, please provide more details about this case:
Are all emails formatted out of order when pasted?
What's the version of your Outlook? (File > Office Account > About Outlook). In order to prevent other problems caused by the version is not updated, please make sure you have upgraded your Outlook to the latest version.
Here are a few steps you can try to resolve this problem:
Check Outlook Settings: Go to File > Options > Mail > Editor Options > Advanced. Under the “Cut, copy, and paste” section, you can adjust the settings to preserve formatting when pasting from other programs.
Copy from Full Email View: Ensure that you are copying from the fully opened email rather than the preview pane. Double-click the email to open it fully before copying the content.
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