Here is the reply I received on the ticket I posted on this issue:
[b][i]It maybe caused by the browser compatibility with avast! add-on. Please remove this addon, for now. The security of your browser/pc will not be compromised. This add-on serves for advisory purposes only and sometimes is conflicting with registry instructions, written by the browsers. Your Internet conection, will be still protected by our web-shield
Please follow the step by step guide to remove the avast! component you need: http://www.avast.com/faq.php?article=AVKB96#idt_0004 ( Browser Protection Box )
[/i][/b]