@Deepak Saxena, Thanks for posting in Q&A. From your description, it seems the PDF is unable to open in Outlook. if there's any misunderstanding, feel free to let us know.
To check on our issue, please collect the following information:
- How did we configure the app Protection policy on iOS? Please get screen shots of the settings.
- How many devices are affected? Is there any iOS working well?
- Please check the Intune Diagnotics logs on Edge for both Adobe Reader and Outlook to see if the "AppSharingFromLevel" and "AppSharingToLevel" are correct.
https://learn.microsoft.com/en-us/mem/intune/apps/app-protection-policy-settings-log
Please check the above information, feel free to let us know.
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