Uploading files as attachments and sending bulk emails are seen as harmful by service providers such as gmail and hotmail. Instead, you can submit your files as a URL with our design tool INBOXBrush.
Click on files button on the top of the page. Here you can upload your files and see the previous files you uploaded. Select the file by clicking on or just drag the file and drop here.
After uploading the file on files page, when you hover over the file you want to upload, you will see the option to copy. When you click this button, the link of your file will be copied, and you can insert this link into a word or image you want.