This Site May Harm Your Computer – Hacked – How To Fix
Blurb by Shaun Anderson (Hobo) -We recently took over a few sites from another company, and a few days later, the dreaded “This site may harm your computer†appeared in Google. Not the best start to a campaign.
If your site is hacked, your supposed to submit a review in webmaster tools, which I always thought should be a bit unnecessary.
Anyway, we cleaned up the code immediately (or rather got the web dev company we took over from to do it), and WITHOUT submitting the site for review, Google removed the malware notice.
Cool.
If I was hacked, I’d probably jump immediately to rectify it. But it’s good to know these malware notices can be removed without notice as quickly as they appeared (although I’m not certain if this is A) widespread and B) if Google wants folks to know this).
John Mueller, a Webmaster Trends Analyst at Google, was kind enough to confirm Google will rescan your website without prompt in the comments below:
We generally rescan them from time to time, but it’s certainly faster if you can tell us when to check
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We generally rescan them from time to time, but it’s certainly faster if you can tell us when to check
. If for instance there’s a reason why you can’t submit a malware review request (perhaps you can’t verify the site in Webmaster Tools without modifying your CMS), it’ll generally get checked automatically over time. Personally, I wouldn’t wait for that, I’d request that it gets checked as soon as I’m sure that it’s clean 
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Thanks very much John that’s what I was thinking
I have had a little experience with this too. I personally think JohnMu is playing down Google’s efficiency at fixing the problem.
A few years ago a client site got hacked, it was a right ballache and required me to submit a request to stopbadware.org and it took over a week to resolve, it was a complete nightmare. However last year the same issue happened and within 24 hours of fixing the problem Google removed the error without me having to make any request.
I also saw several competitor sites have the same problem last year and thay all seemed to fix the problem in around 24-48 hours.
I haven’t seen this too much but is there any thing which looks like a typical thing which sets Google off, what type of thing causes google to show this error (I guess it might be hard to be more specific than Hacked )
Generally speaking, somebody hacks your site, and leaves code that links to another site which does nasty stuff to your computer. YOU need to clean up the code (Google tells you in Webmaster tools the type of code it has a problem with) and then normally, request a review in WMT to give your site a clean bill of health and remove the “This site may harm your computer” message in Google results