After Microsoft updates my system font is now looking like 'graphics'. It is only circles, different kind lines, cubes, corners, triangles, x-marks and so on. Win7 works alright but it is almost imposiible to use that because Internet explorer has also changed it's font unredable.
I found the solution. I had to go to C:\windows\fonts and install the arial.ttf again. That strange font that have cubes, lines and so on is marlett.ttf. Thanks everyone especially to www.prepressure.com-web pages!