I'm having trouble with my email images. This morning, I sent a final test email to myself and a few coworkers. For some of us, the images are showing up, and for others they're not. This has happened in gmail on safari, and on an android phone mail app.

This email is very time sensitive and must be sent in the next 2-3 hours. Before I send it, I want to verify that the images will be displayed correctly for all the recipients.

Do you have any ideas what could be causing this or how to fix it?