1. Click on Start >> Run
2.Type gpedit.msc
3. Under Computer configuration click on windows settings >> Security Settings >> Audit policy
4.From the list of Attributes displayed in the right pane, double-click Audit Logon Events. The Audit Logon Events dialog box appears.
5. In the Audit Logon Events dialog box, click to select both the Audit these attempts: Success and Failed check boxes, and click OK.