During my vacations days, I got nothing to do. So I decided to do some experiment of my own on Windows 10 free upgrade as well as clean install.

First Experiment
Using Dell laptop (preinstalled Windows 7 Starter OEM)

Firstly, I reset to factory default setting using recovery. After that, install Service Pack 1 which I already downloaded before. For your information SP 1 is require for upgrading Windows 7 to Windows 10. After that I Install Windows 10 using ISO created from Microsoft Media Creation Tool and the result are:-

1- Windows 7 Starter SP1 upgrade to Windows 10 Home = Windows 10 Home activated without problem.
2- Windows 7 Starter SP1 upgrade to Windows 10 Home = Windows 10 Home activated without problem and do a clean install of Windows Home = Windows 10 Home again activated without problem.
3- But after I clean install again, meaning I did twice clean install the result is Windows 10 Home is not activated
After call Microsoft Support, It seems there are been cases like where windows is not activated if users perform twice or more clean install after free upgrade is done. The CS said, with free upgrade users cant activated via phone activation since all free upgrade users are given generic keys which the installation ID is not unique like installation ID with retail keys
However, he said Microsoft have been informed about this problem and working a patch on it.

Second Experiment
Using Dell laptop (preinstalled Windows 7 Starter OEM)

Firstly, I reset to factory default setting using recovery. After that, install Service Pack 1 which I already downloaded before. For your information SP 1 is require for upgrading Windows 7 to Windows 10. After that I Install Windows 10 using ISO created from Microsoft Media Creation Tool and the result are:-
1- Windows 7 Starter SP1 upgrade to Windows 10 Home = Windows 10 Home activated without problem.
2- After that, I clean install again the laptop but using Windows 8.1 Pro retail key and do the Windows 10 upgrade process again the result is Windows 10 Pro activated successfully.
3- The same things happen where the first clean install, Windows 10 Pro activated but clean install for two and four times yield the same result which Windows 10 Pro failed to activate
Forget to mention before, the fail activation are not due to Microsoft server overload as the CS said the overload no longer a problem
4. But I repeat the steps
Windows 7 Starter SP1 upgrade to Windows 10 Home = Windows 10 Home activated without problem. After that, I clean install again the
laptop but using Windows 8.1 Pro retail key and do the Windows 10 upgrade process again the result is Windows 10 Pro activated successfully.
Next steps, I clean install with Windows 10 Home not Windows 10 Pro, the result is Windows 10 Home not activated

Therefore I conclude that the activation ID of Windows 10 Pro must have overwritten the activation ID of Windows 1o Home

In the end I suggest the best ways to avoid problems like BSOD, lagging, and so on after upgrade to Windows 10, you may do like me which are

1- Download Windows 10 ISO using Microsoft Media Creation tool and save it on external hdd or another partition
2- Download Service Pack 1 Updates or Windows 8.1 ISO from Microsoft site. These much easier than update via windows update or from store
3- Reset your laptop/PC to factory setting if OEM pre-installed. Clean install windows 7 or windows 8. You may use windows 7 SP 1 straight way but for windows 8 user, you cannot clean install straight away Windows 8.1 unless your keys is for Windows 8.1
4- Don’t install any software yet as well as drivers except for wifi and LAN
5- After reset/clean install, disable windows updates, to ensure windows don’t download any update yet. Now install SP1/Windows 8.1 update which you downloaded earlier before. You may skip this steps if you already reset/clean install to Windows 7 SP1 or Windows 8.1 during step 3
6- Make sure Windows 7 SP1 or Windows 8.1 is now activated. If not activate now via online or Phone Activation
7- Now, mount the Windows 10 ISO using windows built-in mount features or you make the ISO into USB boot using Windows 7 USB DVD Download Tool which also can be downloaded from Microsoft site. Don’t install and mount the ISO using software like Daemon tools, it likely causes the upgrade fail. If the mount features is not available like on Windows 7 Starters, use USB method.
8- Run setup on Windows 10 ISO. The upgrade process time depend on your computer specification
9- After done, you may now install all the latest driver and software. FYI, most drivers for Windows 7 and Windows 8 works well on Windows 10 just in case you can’t find windows 10 drivers for your hardware
10- Last but not least, make sure your Windows 10 activated lol

With these steps you will unlikely face failure during the upgrading process and any problem like BSOD and lagging after the upgrading to Windows 10
If you want to do clean install Windows 10, it up to you. But I think with these steps, it already like clean install Windows 10 right. Anyways it up to you, just friendly remainder, better wait several month until the activation problem is fixed

for VLK/MAK keys, i wasnt sure regarding phone activation as i dont have VLK/MAK keys for windows 10

but for previous version of Windows like XP/Vitsa/7 and 8/8, phone activation can be done as i already test them before using the VLK/MAK keys

As for now, according to CS, only retail/OEM windows 10 keys can do both online and phone activation, maybe later free upgrade can do also. Many users also wonder about activation if hardware changes and Microsoft still hasnt given firm answer as the activation issues still have many flaws

This post has been edited by kiritoffx: Aug 31 2015, 05:48 PM

no need to download all update just SP1 update is enough. then can proceed upgrade wins 10

it shouldnt be a problem. i edi tried with my friends laptop XP-->wins 7--> wins 10 without a hitch. Just make sure ur windows 7 is activated first before upgrade

no issue with wins 10 except privacy issue (google it). wins 10 far more stable than wins 8.1/7 in terms of performance/ ram usage and gaming.

regarding pirated software... no problem as far as i know

1- microsoft outlook is part of microsoft office. In wins 10 , it came with mail app like windows 8/8.1 but with slight improvement in GUI
2- If you don’t take advantage of the upgrade process first, this registration will never happen. There’s no way to enter a Windows 7 or 8.1 key into the Windows 10 installer, nor is there some sort of web form that will give you a Windows 10 key if you provide your Windows 7 or 8.1 key. Sorry — you’ll have to upgrade to Windows 10 before you can perform a clean install.

my hdd only lsat for 5 years before it dead

via windows update or direct from internal hdd (just run setup and choose upgrade or clean install)

Copy entire hard disk to another or migrate OS from HDD to SSD without Windows reinstallation.

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