Stop the Windows 10 Upgrade
Guide to block upgrading to Windows 10:
Step 1: Find and click on the Programs and Features in Control Panel.
Step 2: At the left side, you will get the option to see installed updates. Click on that.
Step 3: After it, you have to locate the specific updates that necessary to be uninstalled. Their numbers execute differently under Windows 7 and Windows 8.
For Windows 7: 3035583, 2952664, 3021917
For Windows 8: 3035583, 2976978
Step 4: Right-click each of the above updates based on your current OS, and choose uninstall. Now you have to restart your computer. It is recommended to put that off until all the required ones is uninstalled, after it again restart your computer to finish the whole process.