Solved..

I bought my Dell Inspiron15 some 2 months ago. As one can see from the screen shots it has a whopping more than 8 GBs wasted as recovery partition. At the time of purchase it had windows 8.1 pre-installed. I opted for free upgrade and now I have Windows 10 Home single language. I have read the section "Installation and Setup" Still I have one doubt as to which method shall I choose for clean install as the partition in screen shot shows EFI. Which method is good for me to re-format and make a clean install?
Thanks and regards,

  

Welcome to windowssh blog, semantsen.

You say the 7.62 GB partition is a waste. That is your Dell factory restore image on that partition. It's there to provide a restore to out-of-the-box state. If you don't value that option then it is indeed a waste. When I got my Dell Inspiron 15 (7000 series) back in June, the first thing I did was make factory restore media using Dell Backup and Recovery. THEN, I had no qualms about doing away with that partition and reclaiming it for other disk use. I also did away with the OEM Diagnostics 40 MB partition - that functionality is on the motherboard itself and can be accessed through the BIOS.

Here is how my laptop (purchased back in June, came with WIn8.1 installed) looked after I recently (doing some testing) took it back to factory restore state and THEN upgradedto the current WIn10 build (10586) using a USB iso made using Media Creation Tool and Rufus:




Here is the layout of my current GPT disk, after clean install (created some few months back starting at build 10240) - I have split my original OS partition into two and am now dual booting both the activated build 10586 and the Windows Insider build 11082:



If, by "which method", you're asking about GPT disk layout (with EFI boot) - which you have now - versus MBR disk layout with legacy BIOS boot, I'm not sure why you'd want to go back to legacy boot/MBR - is that what you're asking about?

Thanks Word Man for the detailed reply. I just wanted to delete all partitions and make new ones as per my need and a clean install. As a newbie i did not know which method to use, GPT or MBR. Yesterday i went ahead and used USB Media creation tool for Windows 10 for my previous edition i.e.Windows 10 Home. I went for GPT offcourse as you have rightly said! Insatallation went very well and is running well. Now the problem is windows is not activating!! I get error code 0x803F7001. (screen shots attached) I am trying but to no avail. Tried to retrieve OEM keys but those are just not acceptable. I do not see any option but purchase a new one. I will be very thankful for any help.

  

Despite the message on your screenshot about being unable to reach activation servers - which, taken at face value, would mean you either have an internet connectivity problem OR the servers are down or too busy (may or may not be likely) - I'm afraid I may have unintentionally misdirected you when I said I used MCT for my clean install.

I see you started with "Windows 10 Home Single Language". As far as I know you must install with the same edition of Windows that you started with and, although it may not be obvious - wouldn't be to me if I hadn't read otherwise, that last part "Single Language" IS significant.

Sooo, my apologies if I was not tight enough with my wording and it cost you time as a result.

If you go to Tech Bench and select the correct edition there, where Windows 10 Home Single LanguageIS an available selection, I believe things will go much more smoothly for you. That site is at this link:

Hopefully, that will get you right back on the track you started down.

NOTE - no need to reformat the disk as you can remove all partitions in the beginning of the install - check out specifically Step 10 and then flow to Step 13 in the tutorial at this link: Windows 10 - Clean Install

There you can delete all partitions and have all unallocated disk space to proceed with a truly clean install.

Thanks Word Man. Its me who messed!! You have given a very good guidance. I will just try a new install. Regarding network it is fine. Can this be something related to DNS server setting?

Thanks Word Man. Its me who messed!! You have given a very good guidance. I will just try a new install. Regarding network it is fine. Can this be something related to DNS server setting?

I kind of doubt that it has to do with DNS - but not impossible. I would say give the exact version match a shot and go from there if any problem remains. Good luck - signing off for the night.

Thanks Word Man for all the help and support offered by you. I finally installed using MCT for usb. I went for single language option as per your instruction. Windows is now activated too.

 

Thanks Word Man for all the help and support offered by you. I finally installed using MCT for usb. I went for single language option as per your instruction. Windows is now activated too.

Ah, good, Semantsen! You're very welcome and I'm glad you have it sorted.