I searched in the Internet, and it says that if a product key is installed on a 2 machines, in order to use the product key on the 3rd machine, I have to deactivate one of the two machine's product key.
May I know what will happen on the two machines if I used the product key on the 3rd machine without deactivating it on one of the first two machines?
According to tableau, you'll get the following error.
"The activation of the fulfillment is denied by the activation policy because max extra activations exceeded."
The best thing to do is to manually deactivate one of the old computers
Hope that helps!