No images load in IE7

i have a site at https://www.epicskitours.com that loads images through css fine in IE and ff2, however, ive started a development site at https://www.dev.epicskitours.com , that initially just used the exact same code as the original. i have edited it somewhat, but the css that calls images is unchanged.

these images are the likes of sidebar backgrounds and logos, and they appear in ff, but not in IE.

ive tried searching through other topics, but none really seem to help.

what can i do?

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