Can anyone provide details of a Dell service centre in London?
Strangely, a Google search doe not come up with any results?
What is wrong with your machine? There should be a number of local computer shops and places like PC World but I don't know if there are any dedicated "Dell Centres".
Windows Reinstallation Guide and Related Wikies See here for other wikies such as Customising and Using Windows 8.1, Dell Wireless Cards and Unofficial Drivers.