I have 2 months ago bought a new Windows 7 Professional 64 bit and installed on my daughter CP, now the computer is broken and can not be repaired -
how do I disable the license code on the old machine, in order to use the installation on another new machine?
Just wipe the hard drive, if that component is still working.
If it isn't just reload Windows on the new machine, always assuming it was not an OEM version that was originally activated with Microsoft online using the original hardware.
Luckily you have a retail copy instead of a pre-installed OEM version. If you can't boot up the broken machine, simply reformat the old drive and then use the product key on the new machine. The only issue is that you'll need to activate by phone, so be sure to check that auto activation is not selected during setup.
See this link on how to activate by phone: Activate Windows 7 by Phone
You should have no problems in activating the retail version of Windows 7 on one machine many ( not any :)) number of times. It is my understanding that you will be required to activate by phone only when that number is exceeded.
Now, if you want to preserve the original activation and restore it on reinstallation without need to activate through internet or phone, you may try Advanced Tokens Manager.
Advanced Tokens Manager - The Activation Backup Solution
Even OEM installations can often be reactivated, but invariably by non-automated activation, as Microsoft cannot legally tie you into using your OEM Windows version on the same old, same old, motherboard and hard drive forever as these components do fail periodically and it's unreasonable of Microsoft to tie in OEM systems to 'perishable' hardware...
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