Hi @Samaher Dhafer Louis Louis
Welcome to our forum!
There is no option in New Outlook to set the pixels of the image signature. To maintain the quality of the image as much as possible, it is recommended that you send it as an attachment and not resize the image.
Please kindly understand that many functions are not designed at present. To get this feature more quickly, I have found a post in feedback collection website and you could vote for it. Many features of our current products are designed and upgraded based on customers’ feedback. You can also make suggestions on that website and hope Microsoft will notice this in the future.
Thank you for your understanding and support!
Is there any chance i can contact Microsoft by a phone call or so?
If you would like to find the root cause, I would recommend opening a support ticket so the support can take a deep look into this issue and do some further troubleshooting. You may contact support by Global Customer service Phone number.
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