Description Details The key will be sent via eMail. Please check the spam or junk mail folder too. CAN'T upgrade from Home system to Pro system, You should download the windows 10 pro system here first , after you installed it, then to activate the code: Please download and install correct edition of windows Click 'Activation' and enter the key you bought.
But note that a key can only be used on one PC at a time, so if you use that key for a new PC build , any other PC running that key is out of luck. Downsides of Using an Old Key When using an older Windows key to activate Windows 10, you may run into complications if Microsoft isn't sure whether you're eligible to update or not. But that seems to be happening less in recent months and years. Don't Activate Windows: I have colleagues who have used non-activated versions of Windows for years without Microsoft ever shutting it down. Microsoft brands PCs running an unactivated version of Windows 10 with a watermark in the bottom-right corner of the screen. A Microsoft spokesperson told me that activating Windows 10 ensures you have a legitimate copy of Windows 10, and the watermark is an attempt to alert consumers that their version could be false.