Error log top_big.gif doesnt exist

I recently upgraded from 2.08 to 2.012.

Though all went well and really like .12 version had issues with SEO as had to turn the add-on off in order to get categories working.

Also when checking logs I did notice that I constantly get the error below from the time i did my upgrades

File does not exist public_html/skins/default_blue/customer/images/top_bg.gif

Is this happening to anyone else or

Does anyone know what this image top_bg.gif is used for?

I did check my files and the image does exist so confused why the constant errors.