Q I use the National Lottery website but recently a page from OpenDNS appears instead. It says that the domain has been blocked, even though I have entered the correct address.

I have tried blocking OpenDNS on my computer and adding the Lottery page to the Trusted Zone in Internet Explorer but neither of these has worked.

John A

A OpenDNS is a useful service that can help block inappropriate content and phishing attacks. It works by replacing the DNS servers used by your internet service provider (ISP). These servers convert friendly web addresses such as www.computeractive.co.uk into the numerical address used by computers.

OpenDNS servers will not do this for harmful websites and offer a more reliable form of blocking than many alternatives. You can customise how OpenDNS works but you will need to register in order to do so, otherwise you are stuck with the default settings.

Visit OpenDNS. Click on the Create account link at the top of the page. Click on the Sign up button in the OpenDNS Basic box, fill in the bottom form and click on Continue. Click on the OpenDNS logo at the top left of the window and click the Dashboard link at the top of the next page to access the settings for your account.

OpenDNS recognises your account by the internet address of your computer, known as the IP address, which should be shown in this settings page. Click on the ‘Add this network’ button. Give it a name, leave the option ‘Yes, it is dynamic’ selected and click on the ‘OpenDNS Updater for Windows’ link.

This software will keep OpenDNS aware of any changes to this address so it can apply your preferences to the service. Click on the Done button.

When it has finished downloading, install and run the software. Enter your OpenDNS username and password when requested and click on Sign In. Click on the ‘Refresh network list’ button and the network will appear.

Close this window and it will disappear to the Notification Area. Make sure you give it permission to connect to the internet if your firewall asks. It will occasionally alert you when it has updated the OpenDNS settings but you will not need to do anything.

Return to the OpenDNS settings page and click on the IP address of your network to access the settings. You can set the overall level of blocking in the Filtering level section but exceptions for individual websites (also known as domains) can be set at the bottom. Enter the address of the website in the text box, select Never block and then click on the ‘Add domain’ button.

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