The online world can be just as safe and comforting as the real world – or just as menacing. While tons of information and sites on the internet are safe, factual, and relevant, there are also a large proportion of them that are quite the opposite: unsafe, bogus or irrelevant, or outright malicious.

Most search engines, especially Google, take extra measures to protect their users from being exposed to such malcontent by making sure that websites which appear to be harmful do not get the exposure they require to attack large numbers of people, mostly by hiding those pages deep, deep down in the search results. In some extreme cases – when sites are really, really bad – the website’s IP address can be blocked or blacklisted.

Visitors who make their way to such websites will see a warning message: “Access Denied” followed by a brief explanation.

Is this happening to your website? Sometimes, even well intentioned site managers can face these issues, leading to headaches, loss in revenue, even total site shut down. Don’t be caught by surprise if it happens – figure out why and get it fixed!

Here are the most common reasons why IP addresses may be blacklisted. Sound familiar?

1. You are facing legal issues. Whether you’re being sued by another business (copyright infringement, etc.) or someone thinks your site is dealing in illegal trade or distribution of harmful or dangerous materials, the law will eventually shut you down. Period.

2. You are hosted next to a rogue site. If you opted to host your site on a shared hosting solution, your site may be on a server along with other sites guilty of spamming, selling illegal goods/services, or showcasing content that is considered hateful, inappropriate, or abusive. This means both your sites will have the same IP address and, if theirs gets blocked, yours is likely to get blocked, too.

3. You are accessing the site from another country. Many countries in the world are notorious for censoring the information their citizens can access. Whether it’s for political reasons, security reasons, cultural reasons, etc., a country could have their central ISP block a site on a temporary or permanent basis. People who try to access the site may well find themselves facing charges that could send them to jail for a very long time.

4. You’ve been hacked. Sometimes, you may be punished through no fault of your own. If you happen to be unlucky enough to be hacked, and the hackers have infected your website with malicious code, script, or content, you could find your site blacklisted. Of course, you, your web hosting provider, or both could be blamed for not putting the necessary security measures in place.

5. You tried blackhat SEO techniques. Google is very strict about punishing site owners that try to fool its SEO algorithms and you could be penalized gravely if you try to sneak past them on your way to the top of their SERPs. Don’t even think about it – sooner or later, they’ll find out.

6. It’s an inside job. Many business leaders know that irking the tech staff will, at one time or another, cost them dearly. Statistics show that most hacks are done from within the company itself. If someone on your tech staff isn’t happy with the ways things are, they could wreak havoc on your website by inserting some extra and unnecessary code. This is especially true if you have given them their pink slips.

Now, you may have an idea of why your site was (or is) blocked. More importantly – what can you do to fix it?

First, test to see that your site is indeed blocked. To mimic a visit from outside the country, you could use VPN software or simply ask someone living abroad to send you a screenshot of what they see when they type in your domain name.

You could also do a google search for site:[yourdomain.com]. If no results are returned (especially if you already had it indexed), then there is a good chance you have been blacklisted.

Luckily, Google has tools that can really help you navigate the blacklist world. Their Webmaster Tools will help you a lot, so make use of them. One particular tool even lets you know if your site has been hacked, while another lets you know if you’ve been blacklisted due to copyright or DMCA claims.

Talk to your web hosting provider and see if they can’t move you to another server. If they won’t, find another provider – and fast.

Check through your code and scripts to see if there isn’t anything that isn’t supposed to be there, or that you didn’t put in yourself. If you’ve got someone you trust on your tech team, they can help you figure this out, as well.

Get rid of illegal products/services and unacceptable or offensive content. If you aren’t willing to do this, then your site will not survive.

Finally, re-submit your site for indexing. Keep your fingers crossed.