Do you have your anti virus set to scan your files on boot? Perhaps it is scanning the file. Check your startup tab in msconfig and see what's going on. Uncheck everything except your AV and then boot.
Change the world. Of one person. Today.
If your equation requires either a complex combination of variables to get the desired result OR you can't seem to get the result regardless of the variables....it ain't your variables, it's your constant.