Most of the themes of prestashop does not compatible on IE browser but it works in other major browser. One of the mojor cause that IE support only 30 css files and does not care other css files . So IE Browser loads only 30 files in browser memory . Now we are going to give best solution to load all css files in prestashop.
1. Log on backoffice of your prestashop
2. Click on Advanced Parameters > Performance
3. Now on “CCC (Combine, Compress and Cache) ” form fieldset you need to select “Use CCC for CSS. ” option of “Smart cache for CSS ”
4. Click on save button.
Combine, Compress and Cache do all css files into single css and load single load so. IE Browser will load all css and looks great in IE Browser. If you are getting still Design Error on IE Browser then you need to do IE CSS Comment Hack to solve the problem. http://www.quirksmode.org/css/condcom.html