Also depending on which web Host you have (GoDaddy for sure) you need to add the folder name where the domain exists in the RedirectMatch code. This can be confusing. The folder name is: /example.com and the website domain URL is also example.com.
Example:
RedirectMatch 301 ^/example.com/index.html$ http://example.com/
Reference: http://forum.ait-pro.com/forums/topic/go-daddy-redirect-htaccess-code-no-longer-working/