I finally replicated the issue, it seems like it only happens when you press the “search button” more than once. I was asked to wait for 4 minutes but when I typed in my word and clicked “search” everything worked.
Mmm...I don't know about that; the search function has always been pretty damn slow for me, and I did figure out early on that hitting the button more than once gives you the big ol' stop sign tread93 described.
It doesn't seem like 4 minutes - but only 4 seconds.
You are searching too quickly. Wait 4 seconds. (There is a Google-based search engine on the search page that does not have this limit.)
So far ninjastic has helped me search faster than the forum search feature. I almost forgot that the feature existed - that's because I never use it as often as I do ninjastic. The best suggestion is to use ninjastic for fast searches - I and many other users have switched to it.