I'm guessing you are using IE? There have been a few people who have had that problem - a small set of IE users. It appears that Microsoft has some type of security "enhancement" that is not working quite right. It also appears to have something to do with the trillions of options one can turn on or off in the browser.
The truth is
Google Advanced Search using this domain name is FAR superior to the SMF search anyway. And, you won't have problems with your browser.
This cannot be fixed here because it's not a joomla.org problem. Thankfully, it shouldn't matter since there is a better approach for all of us to use when searching, anyway.
HTH,
Amy
