Did anyone else freak out this morning when they tried to click a link on Google and got the Malware "This site may harm your computer" message? I was in a blind panic at 10:27, thinking my computer had contracted a virus, and trying to imagine a world where I couldn't Google everything. By 10:33 the situation seemed to have rectified itself, thanks to my quick-thinking of refreshing the page every three seconds and crying. By 11:00 I had forgotten the whole mess. But it wasn't my computer that was the problem, it was the entire Google mainframe: a mistake on such an enormous scale that the idea of the infallible search engine failing seemed less likely than me sleep-typing and downloading some horrible virus. In case you too were doubting your sanity, the official Google blog explanation, after the jump.

What happened? Very simply, human error. Google flags search results with the message "This site may harm your computer" if the site is known to install malicious software in the background or otherwise surreptitiously. We do this to protect our users against visiting sites that could harm their computers. We maintain a list of such sites through both manual and automated methods. We work with a non-profit called StopBadware.org to come up with criteria for maintaining this list, and to provide simple processes for webmasters to remove their site from the list.

We periodically update that list and released one such update to the site this morning. Unfortunately (and here's the human error), the URL of '/' was mistakenly checked in as a value to the file and '/' expands to all URLs. Fortunately, our on-call site reliability team found the problem quickly and reverted the file. Since we push these updates in a staggered and rolling fashion, the errors began appearing between 6:27 a.m. and 6:40 a.m. and began disappearing between 7:10 and 7:25 a.m., so the duration of the problem for any particular user was approximately 40 minutes.

One misplaced backslash makes all the difference folks. Please Google techies, don't drink and program.