Hi @abh
Welcome to our forum!
For our better research, please provide more information about this case:
Is this an email you sent or an email you received?
Have the same problem in Outlook web?
Do other emails with pictures have the same problem?
If you received the email, it is recommended that you confirm with the sender. Because it could be the sender such a setup.
If you sent it, it is recommended that you follow the article steps to resize the image before sending.
Alternatively, you can follow the steps below to optimize the images in your emails. Clicking File > Info, selecting Resize large images when I send this message under the Image Attachments section, and clicking Send.
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