Dreamweaver CS4 - Background Image Disappears when Tested in Firefox

Hi, everybody
How are you?
Don't know what to do, I have the background image saved in the root folder, it's there in the Dreamweaver CS4 window. When preview in browser (Firefox), it disappears, not there.
It shows up in Internet Explorer but when I do a hard refresh, Shift F5, it disappears also.
At wits end, don't know how to fix it.

Anybody that can help?

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