Is horizontal css menus compatible with IE browser?

Q: I bought your the software CSS3Menu version

I would write to you because I have problems when menus are installed.

IE8 problem: the titles are cut up menu (see screen-copy) and responsive menu does not work on IE8 .. it does not fold.

A: Unfortunately, IE browser v.6-8 doesn't support CSS3 standard (support of Css3 was added in IE v.9).
That's why rounded corners and drop shadows on the sub-menus will not showed correctly in Internet Explorer v.6-8 browsers.
"The dropdown also works on non-CSS3 compatible browsers such as IE7+, but the rounded corners and shadow will not be rendered."