I have Windows 8, all sistem requestments but I installed SL and is not working.

[Solange Clarence]

It says "Second Life is unable to run because your video card drivers did not install properly , are out of date , or are for unsupported hardware. Please make sure you have the latest video card drivers and even if you do have the latest, try reinstalling them. " 

I tried reinstalling and I continue to recive this message. 

What can I do?

[Syo Emerald]

Mhmm...maybe check what the message says?

Find out where your grapic card is from (for example, Nvidia). Go to the website of the company your card is from and search there for the latest driver for your card.

[Rolig Loon]

See KarenMichelle's comprehensive advice regarding Win 8 installation, repeated many times here.  For example, at http://community.secondlife.com/t5/Everything-Else/On-window-8-dell-keep-booting-me-off-the-SL-we-need-to-update/qaq-p/2573458