As a free upgrade to Windows 10 will end on 29 July 2016 I tried to update my laptop immediately before its free offer ends. To upgrade for free just go to the Microsoft website and you will see a free upgrade banner somewhere on the page. Just hit the free update to the Windows 10 banner and you are going to be guided step by step.
In my case, the process took about 2-3 hours (depending on how fast your internet connection). It will first download and then install windows 10.
After boot, it will try to update the software and the problem begins, the update stuck even after I wait for hours.
There are several solutions out there to this problem but the one that worked for me was trying to fix the update service. We can detect this problem before Windows 10 update.
In windows 7 or 8 Make your windows update service is working correctly by opening Internet Explorer and clicking Tool>Windows Update and try to update your windows if you are able to update some patches from there, then you will not have a problem updating to Windows 10, but if you are unable to update using windows update you will face the same problem above.
Mine is Windows 7 Pro edition with SP1 installed. To check what version you got, click Start, right-click the Computer icon and click properties.
How I Overcome This Problem?
Install System Update Readiness Tool for Windows 7 (KB947821) from here
If you are like me using Windows 7 Sp1 then you can use the direct link below
The file size is about 230Mb. After installing the update above make sure you can update via windows update successfully. If still cannot restart your computer.
When you are able to use windows update, you are ready to update to Windows 10 without a problem. Have a nice try.