How do I protect my Windows PC? Windows Defender has been switched off on my new laptop pre-loaded with Windows 8. I understand this a common OEM ploy to promote their software. I have found no way to re-enable it. Can you help? Peter Maine, by email Those free trial and demo programs, unofficially dubbed "cr*pware," and included with many PCs, can be a real nuisance. One of the first things I do on a new Windows PC is install a free program called SlimComputer (slimcomputer.com). This helps you safely remove or disable the programs that you do not want - most of them, probably - including any security programs that may have switched off Defender or Microsoft Security Essentials. Once that's done you can re-enable it by going to Control Panel > Windows Defender or simply type Defender into the Search box, click the Settings tab, check "Turn on real-time protection" and click Save Changes.