If you have Windows Professional edition then you should ensure that the Remote Assistance and Remote Desktop features are disabled. These features are very helpful if you have a problem and you want your technician to remotely help you, but if they are unnecessary, they can create a security hole in your computer. If an attacker has compromised one of your accounts, he can easily log onto your system from a remote location.
To disable the Remote Assistance and Remote Desktop features, right-click on My Computer or This PC and select 'Properties', then click on 'Remote Settings'. Uncheck the 'Allow remote assistance connections' and 'Don't allow connections to this computer' checkboxes, then click Apply.