When you upgraded 7 to 10 a digital licence tied to your PC's hardware was recorded on Microsoft's activation servers. Activation based on your existing digital licence is automatic. You don't need a product key, if asked for one click 'I don't have one' and carry on. You shouldn't be asked for one for a repair install, only if you tried a clean install (ie. keep nothing).
I downloaded using the media creation tool and it took forever(by forever I mean more than 8 hours non stop) And in the end it said some files couldnot be downloaded.Now I used a little trick online and downloading the iso which will also take a long time but atleast I can pause it or stop it when I want to. One thing I am feared is that my computer has been working nonstop since yesterday and it might get over heated or something like that..Also will it damage/corrupt the iso file if I pause it for some time and then continue the download?
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