You can't even know how much I am pissed off. [EDIT: read it]
Ok, so last Friday, I bought Windows 8 Pro (boxed edition) and I installed it on my main desktop computer. Everything went well. This morning, I tried to install it on my laptop and it told me that I can't use the product key on more than one computer. Are they insane or what? With Windows 7, never had this issue and I installed it on a few computers using a single product key. Since I have another desktop beside my laptop to upgrade, do they really want me to put 240$ on Windows? How is this supposed to be acceptable?
EDIT: So, I called Microsoft and it seems that my Windows 7 license was a promotional edition supporting 3 computers and I was not aware of it but it was just working when I installed it on my 3 computers.
Now, it seems that I was wrong from the beginning and normally, it's 1 license/computer and I was not aware of this since I never knew I had a promotional edition of Windows 7 supporting 3 computers.
Then, I present you all my apologies. I was wrong and this is not an issue but just me misunderstanding a situation.