I'd like to suggest that this thread be deleted. It seems to be misleading a lot of people.
Sending an epub to your Kindle after renaming it to .png via Amazon does convert it and it's readable on the Kindle. Copying it from your computer with a .png extension doesn't work. I saw this the other day on The Ebook Reader Blog, article at this link:
http://blog.the-ebook-reader.com/201...o-your-kindle/
I tried it. It failed. Someone in the comments suggested that the comma in the file name might have prevented it from working. I removed the comment, emailed it again and it worked.
When I saw this today on The Digital Reader it also implied that you could simply copy the renamed file to the Kindle. I tried that and it didn't work. I hadn't really expected it to but I thought it was worth trying. He linked to this thread which is as misleading as the article although a few of you do try to straighten things out.
Leaving this thread in place is going to cause a lot of people a lot of frustration and I really hope someone with god-like powers here will remove it and then replace it with an announcement about how it really works.
Barry