Fire fox won't open after installing update. But it shows in my task manager as running

Firefox won't open after installing update 3.6.6 Solution page says problem has been solved, but the solution has been removed. == This happened == Every time Firefox opened == After installing update 3.6.6 == == User Agent == Mozilla/4.0 (compatible; MSIE 8.0; Windows NT 6.1; Trident/4.0; SLCC2; .NET CLR 2.0.50727; .NET CLR 3.5.30729; .NET CLR 3.0.30729; Media Center PC 6.0)