you need to close, and restart the browser after doing so 
I know that
I've done it even twice with no expecting results
. Any suggestions?
Does your ISP (or you) use an Internet Proxy (a cache of recently requested pages, gives the impression of faster access), if so it is possible that it has not been updated.
Try this when you have the avast.com page displayed (if it's still the old one), press the F5 key this forces a refresh without using the local cache, press the Shift key and click the Refresh icon on your browser, this also bypasses the local cache.