At the Design step of a newsletter, click on the 
button to upload a new image.
In the Image properties window, click on browse server.
Drag and drop your picture or click on the “send” button to search it in your computer.
Take care of the image’s size and name :
- The image must be less than 1200 px. If it's more, it will be resized automatically update langs set en=lost of quality) or it could not be upload.
- Some of email applications update langs set en=like Outlook), display images in their real dimentions and don’t care about html code to resize them. For best optimization, we recommend to upload images at the right size as they will display in your newsletter.
- The image name can not contain spaces or special characters. You can use underscore.
For example :
- image.example --> not correct
- image_example --> correct
- image de montagne --> not correct
- image_de_montagne --> correct