Please locate your product key first.
COA sticker may contain the concealment panel which consists of a small clear label with removable silver scratch-off material that has been applied to conceal a portion of the 25-characters of the product key. Do not try peel off or scratch the small clear transparent label. Please use a finger nail to gently scratch the silver surface off - start from the middle, not from the edge.
- Select the Start button, then select Settings > Update & security > Activation
- Select Change product key, and then enter the 25-character product key.
If you still unable to activate you might have mistyped your product key. Try retyping it.
Windows product keys are limited to the following lists of valid and invalid product key characters;
Numbers : 2, 3, 4, 6, 7, 8, 9
Letters : B, C, D, F, G, H, J, K, M, P, Q, R, T, V, W, X, Y
Numbers : 1, 5, 0
Letters : A, E, I, L, O, S, U, Z
Attempting to enter any unacceptable characters, during product key entry, may result in an error
If above suggestion did not help you may need to activate Windows by phone, type SLUI 04 in the search box on the taskbar, select SLUI 04, then follow the instructions on the screen to activate Windows.