how can i fix my desk top white screen?

That's a rather cryptic question.
We need to know whar operating system you use and it's version.

You say that your screen HAD white... That's in the past tense. So, it looks like it's no longer the case.

What are you trying to do? What do you want to access? You want to join WHAT?

You may be experiancing a dull joke: Someone set your wallpaper to an all white image, with a black background making the icon's text also white, and set your text colour to white. He may also have hiden your icons...

Electro
April 2012