title: value of environment variables keep disappearing
body: <p>Lately I'm having this weird problem. I added a path to the lib user variable of the windows environment variables.</p>
  
  <p>I did this by right clicking my computer -> properties -> advanced -> environment variables -> double clicking on "lib" and adding <code>;</code> and the wanted path at the end. </p>
  
  <p>I'm adding the following: <code>D:\Program Files\Microsoft SDK\Lib;C:\Program Files\Microsoft Visual Studio\VC98\Lib</code></p>
  
  <p>Everything worked fine (I did it a long time ago), but suddenly every now and then, lately every few minutes, after running visual studio, the path that I added disappears and I can't compile my programs until I add the path again. (It does not matter which program I'm running.)</p>
  
  <p>Why does it happen? Is there a solution?</p>