python not found problem

When I start blender it says that
“No installed python found”

    i looked around in the forums for this problem cus I "obviously" have python installed.  The most common way to solve this problem is by 

going to    my Computer -> Property -> Advanced tab -> 
                        Environment Variable -> user Variables

 and then press new 
      variable name  :    PYTHONPATH
      variable value  :  


  then it <b>should</b> work ........

but, i'm blender still claims that no python is found......

i'm using Pyhton25, latest blender version,  and i checked the spelling ,  i just have no clue what else to do... plz help

The current version of Blender is compiled with Python version 2.4, you may need to install that version of Python and point to it.