I was able to download the new ISO X64 Professional Windows 10 software this morning. The following test was run on a Dell E6500 Laptop. Install the ISO and skipped the Product Key to start. Windows 10 loaded and completed successfully. Restarted the laptop and it asked for a Product Key, gave it the Windows 10 Professional KMS Client key which started with W269N.. ended with ..T83GX. Windows 10 didn't like the Product Key because there was no KMS Client on the new Dell install. Loaded up my old version of KMS 2.5.1 and executed a Windows Client Activation. It accepted the Windows 10 Product Key and activated the new system. I then ran the Microsoft License Manager, and it shows that the KMS 2.5.1 with the Product Key from Windows 10 Professional is a legitimate key. Hope this information helps some others.
I really can't comprehend why so many people are dicking around with KMS when you already own a laptop that came with a Windows 7 Professional COA in the battery compartment. You're already LEGALLY LICENSED to run Windows 7 Professional which means you're LEGALLY LICENSED to run Windows 10 Pro in either an upgrade version (which you have to do one time) or clean installs (limitless) so why are you insisting on mucking around with some KMS bullcrap? The latest BIOS update for the Latitude E6500 has a SLIC 2.1 table in the BIOS so again, you're covered - all you have to do is a clean install of Windows 7 Pro on the machine (simple enough to do without issues) then upgrade that to Windows 10 Pro, again without any issues. You don't even have to put in a Product Key, ever. After you do the Windows 10 upgrade install, wipe it and then clean install Windows 10 Pro - again, without putting in the Product Key either time because it asks you twice to do it - and when you get online the clean install of Windows 10 will be activated. What is it with you people thinking you're getting something over on Microsoft sometimes, good lord, get a grip on things, kids.
JeanYuhs ; Perhaps some people looks for a walk-around to avoid a compromise with M$, 30days ahead, about to keep or not Windows 10 free for 1 year. Do you think that the 2nd year will be free ??? In my case I'm still waiting for the cash-back of my payment of one Windows 95 License, according to my complaint regarding the poor performance and the promises not met of this OS. So, I will take W10 in return. Also, this forum is full of questioning people / developers / pseudo-developers / etc. It is not exclusive for "plain installers" that are welcome, of course. There is a wild world out there ..........