Top 7 Security checklist for Microsoft Windows 7
1. Action Center
Use Action Center to make sure your firewall is on, your antivirus software is up to date, and your is computer set to install updates automatically. For more information, see How does Action Center check for problems?
2. Windows Defender
Use Windows Defender to help prevent spyware and other potentially unwanted software from being installed on your computer without your knowledge. For more information, see Using Windows Defender.
3. User Account Control
User Account Control asks for your permission before installing software or opening certain kinds of programs that could potentially harm your computer or make it vulnerable to security threats. For more information, see What is User Account Control?
4. Backup and Restore
It's important to back up your files and settings regularly so that if you get a virus or have any kind of hardware failure, you can recover your files. For more information about backing up your files, search for "back up" in Help and Support.
5. Windows Update
Set Windows Update to download and install the latest updates for your computer automatically. For more information, see Install Windows updates in Windows 7.
6. Windows Firewall
Windows Firewall can help prevent hackers and malicious software, such as viruses, from gaining access to your computer through the Internet. For more information, see Windows Firewall: recommended links.
Of course, Antivirus is mandatory.