METHOD 1 – Activate your Windows 10 using CMD ( Command Prompt) So, here are we to help you resolve this issue permanently. Also a watermark keeps on appearing at the lower-right screen and of course it would be very annoying to have the watermark on screen and also you can’t personalize your own device or pc. When later anytime after you reinsta ll your Windows 10, it will ask you to activate the Windows. Follow the tutorial to Permanently Activate Windows 10 (any version) absolutely free, Here are the top 4 ways.