Which OS?
Which OS?
And this was the issue you faced. The beta releases following the 10 launch had certain problems. The most recent version (10565) is quite solid and introduces new features. You might want to try that release. Are your Windows 7 installation a pirated copy? If not, you can proceed with an upgrade. Some users have even obtained the genuine build from Microsoft on pirated Windows versions. Otherwise, simply purchase a license key.