New versions of images won't upload properly

[Guest]

I am having trouble uploading new versions of images with the same file name, and I cannot figure out why.

 

http://obviate.us/catalog/index.php

 

You can see the corners of the blue side bar headers do not match the color of the rest of the header. I changed the color of the headers in my CSS file, and the corners are GIFs.

I changed the colors of the corners in Photoshop to match the headers and saved them with the same file name.

I tried saving the GIFs as both RGB and Indexed Color (what they started out as) after editing.

I made sure they were uploaded to the correct folder.

 

However, when I upload the edited GIFs, the image doesn't change to the new one when I reload the page.

While trying to figure out where the problem was occuring, I realized that when i save the edited image and open it again, it looks fine. but if i upload it to my site, then drag that version back to my desktop, it's the original, unedited version.

 

 

I've been able to edit these very images in the past with no problems.

 

any ideas as to why this may be happening?

[Guest]

on another forum someone suggested i try changing the file names - but this may be kind of a pain (especially if it doesn't work!) so i'd rather it be my last resort....

any other ideas???