Thank you for posting your query on Microsoft Community forums.
I understand that you are unable to see the attachments in the mail sent from Iphone in mail app.
Please answer the questions before we proceed with the troubleshooting steps.
1) Are you able to see the attachment, when you view in email from Internet Explorer?
2) Are you able to view the attachments sent from other email clients?
We would suggest you to try the following methods.
Run the app troubleshooter which is mentioned in the link below and also perform the steps which is mentioned in the article.
What to do if you have problems with an app
Also refer to the link given below.
Mail: Frequently asked questions
Hope this resolves the issue. If issue persists you can write back to us with the details and we will be happy to assist you further.
Did this solve your problem?
Sorry this didn't help.
Great! Thanks for marking this as the answer.
How satisfied are you with this reply?
Thanks for your feedback, it helps us improve the site.
How satisfied are you with this response?
Thanks for your feedback.