The great and mighty Google screwed up royally Saturday morning plastering practically every one of its search results, even its own sites and services, with the warning, "This site may harm your computer," making every web site in its database unreachable and creating general mayhem.

Anybody doing a Google search between 6:30am and 7:25am West Coast got the message.

It took Google a couple of hours to chalk it up to "human error."

After seeming to blame StopBadware.org, it ultimately explained that it works with the consortium on maintaining a list of sites known to install malicious software on visiting computers. It said it updated and released such a list Saturday morning except "the URL of '/' was mistakenly checked in as a value to the file and '/' expands to all URLs."

Since Google pushes these updates out in a staggered and rolling fashion, it figures "the duration of the problem for any particular user was approximately 40 minutes."

See here for its updated explanation.

Since the warning message referred millions of people to StopBadware.org for more information, the consortium's computers were in turn overwhelmed.

Marissa Mayer, VP of Google search products & user experience, promised to "put more robust file checks in place to prevent it from happening again" since it's amazing that one little rogue keystroke could create such havoc.

The interruption underscores the danger of a Google monoculture. Yahoo can thank its lucky stars. 

• Human Error Causes One Hour's Google Search Chaos