Spot Unauthorized Login Attempts in Windows Vista

Unless you examine the Windows event logs frequently, you may never know that someone has been trying to surreptitiously access your PC. To help solve that problem, Windows Vista contains a new feature that allows you to view previous login attempts, along with the time and date they were made. If you spot any attempts or actual logins made without your knowledge, it is likely that someone else has been trying to use your PC. To enable the feature, follow the steps below in Windows Vista:
1. Backup your registry using the steps given in article R11, which you can also find here: http://www.windowsadvisor.co.uk/reg_backup.html
2. Press [Windows Key] + [R], type REGEDIT and click OK.
3. Navigate to the registry entry: HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Policies\System
4. Double-click on DisplayLastLogonInfo. If it doesn’t exist right-click on a blank area of the right-hand panel and choose New > DWORD Value. Name the new DWORD DisplayLastLogonInfo.
5. Double-click DisplayLastLogonInfo in the Value data field, enter 1 and click OK.
6. Exit the registry editor and restart your PC for the changes to take effect. Once you log in you will see a screen displaying information about the previous login attempts.