A “bug” that caused the Google search to treat search results as malicious has been put down to “human error” by the search engine.

Uses reported that almost all Google search results conducted within a 55 minute period on Saturday January 31 returned a warning that the link contained some form of malicious software, with alerts stating that the site “may harm your computer.”

Users who clicked on their preferred search result were advised to pick another one.

The search engine, whose corporate slogan is “Don’t be Evil”, later put the error down to a simple coding error.

“What happened? Very simply, human error,” wrote Marissa Mayer, vice president, search products and user experience, on the Official Google Blog.

“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.”

She added: “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.

“We will carefully investigate this incident and put more robust file checks in place to prevent it from happening again,” Ms Mayer wrote.

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