How do I know which links to remove when I get an “unnatural links” message?

Matt's answer:

MALE SPEAKER: Today’s question comes from dbizzle in Los Angeles, who wants to know “Google Webmaster Tools says I have ‘unnatural links,’ but gives little help as to which specific links are bad. Since I have never purchased links, I don’t know which ones to have removed, and I’m scared of removing good ones, which will hurt my traffic. Suggestions?” Excellent question. So we’ve tried to become more transparent. And when we were saying links were affecting our reputation of the entire site, we would tell people about that. More recently, we’ve been telling people and opening up and saying, hey, we still like your site– your site overall might be good– but maybe there’s some individual links to your site that we don’t trust. Now, the problem is we weren’t, at that time, giving specific examples. So one feature that we rolled out is the ability to sort by recent discovery of links, so you can actually get the date when we discovered a link. So if you sort that way, you can look for the recent links. But a feature that we are working on and that we are in the process of rolling out, which I’m pretty excited about, is that we will actually– will basically give you examples. So as we’re building the incident, whenever a webmaster analyst or something like that is saying, OK, these are links not to trust, they’ll include an example link. And you might get one, you might get two, you might get three, depending. But basically, it will give you an idea of the sorts of links that we are no longer trusting. Now, it’s not exhaustive. It’s not comprehensive. But it should give you a flavor. Is it a bunch of widget links? Were you doing a bunch of keyword rich anchor text in article bank, article marketing type stuff? Maybe you weren’t trying to do paid links, but maybe you hired an agency and it turns out they were doing paid links and you didn’t realize it. But I would look in the text of the messages. Over time, we’re working very hard on trying to include an example or two link, so that when you get that message, you have an idea of exactly where to look. And I hope that that’s helpful.

by Matt Cutts - Google's Head of Search Quality Team

Original video: