start button missing

[sungleeins]

how to get back stat button and task bar

 

[Xttony]

Did you accidentally change the taskbar location and enabled auto hide? Although it is unlikely check it by pressing the windows button on your keyboard.

 

[Branden]

Sounds like your computer got infected with Windows 8.
to get your start button back either downgrade to Windows 7, or install a program called "Start Menu 8".