Windows 10: Windows 10 retail key said not valid on my new pc but i still can reactivate on my old pc

so i just finish building my new pc i have a old pc that have a retail win10 on it and i want to reuse it on my new pc i deactive unistall in the cmd and all but when i paste the key on new computer it said it unvalid but when i try to active it again on my old computer is just work ??? i download the right version of win10 on both computer which is win10pro and check my key legit or not with microsoft pid viewer as well the key is still link to my microsoft account or do i need to logout of that as well

:)

 

Upgrading a PC and Retail Keys

If I build a new PC and activate Windows 10 on it with my old Windows 8 key which was used on the old PC, will the old PC remain activated?

 

Transferring of Windows Retail Key from OLD PC to New PC

Hi there,

I am having windows retail key installed in Old Laptop. Now I want to transfer windows key to newly procured desktop. Could you please help me to transfer the key to new PC to activate it.

Regards

Sameer M

 

Very hard to reactivate windows 10 Retail key to new pc

Yes, I am aware of this in the first place. From the beginning, this retail key is activated in my old system which i recently sold it to my friend without hard disk. The key is activated and link it to my microsoft account when i used this PC. So, afterword,
assembled my new system by myself, installed new/ fresh windows and used my retail key, but not able to activated. On the otherhand, my friend put new hard disk to my old system he bought and install windows 10 newly and as soon as he connect to internet,
the windows is activated automatically at the same time. Tried few trick on the old system like unlink the account, uninstall the key by command etc. No one a single trick worked. So, posted on this community hoping there might be answer.