windows not genuine

bradas128

Reputable
Jan 18, 2017
15
0
4,510
After reformatting and reinstalling windows i am now getting a black desktop screen and annoying popups saying 'windows may not be genuine'. I tried activating the product key but it says my product key is not valid. This happened before i reformatted my pc though, so i already have this 48 number key to enter somewhere, i just dont know where. the activation window is just telling me to check my key and retry.
 
Is this an oem computer (Dell, HP, etc) or is this a custom built PC?

If custom built did you buy a copy of windows that came with a disk (or flash drive) and a COA license sticker? Or did the company just send you an email with a license key?
If it is the latter then your key is not genuine.