Windows 10 Tutorial to dual boot 8.1 and 10

[maybe]

I'm sure the gurus know how to do this but it is a daunting task for normal users. So, it would be great if one of the many gurus here could provide step by step instructions for the rest of us to go from an existing 8.1 oem factory installation to a dual boot 8.1 and 10.

I've done some research and assume the steps would include

1. Discovering the existing factory installed W8.1 serial number
2. Image backup of the w8.1 (and create an install iso?? How? )
3. Installing the free w10 update

that part is relatively easy, but the following steps need how to advice:

4. Discover the W10 serial number
5. Create an install DVD for w10. *How?
6. Do what is necessary to get a dual boot.
Maybe
EasyBCD
*But preferably a free tool
7. Somehow reinstall the backed up W8.1 into the dual boot system
8. Use the W10 DVD to add w10 as a dual boot.

**In partitioning for the 2 Windows systems, how large partitions for each?
**Can they share a data partition?

"Step by step" instructions by the experts would be so-o helpful to us newbies and make the transition much easier.

Thank you!

 

[Saltgrass]

Maybe you have some special circumstance regarding your license, but the Windows 10 upgrade absorbs the Windows 8.1 license and you are not supposed to use 8.1 any longer. The upgrade itself is supposed to remove 8.1 for that reason.

You can purchase both OEM and Retail versions of Windows 10.

 

[ussnorway]

1. Discovering the existing factory installed W8.1 serial number

Pointless as the 10 upgrade finds it by itself and the key is then locked.

2. Image backup of the w8.1 (and create an install iso?? How? )

these are more than covered already

6. Do what is necessary to get a dual boot.

a new key i.e not the one used in the 10 upgrade... so another 8 or 8.1 key

**In partitioning for the 2 Windows systems, how large partitions for each?

I build on 100g per system... you need the windows, programs, free space for page files and of course patches

**Can they share a data partition?

Yes they share files just file but not programs and not the documents folders i.e my music, my pics etc... both systems can and should have most of these files on another (non-c drive) folder that they both use

 

[maybe]

Thank you for taking the time to reply.

Do I understand correctly that the free upgrade license means that I can only have windows 8.1 - or - Windows 10 on the laptop - but not both in dual boot - unless I purchase a second license?

If so, my idea of using dual boot to "try" 10 is not a practical option. (unless I misunderstood).

So to try 10 I have to go all in and if too many problems appear my only option would be to restore the previous os and hope it comes back correctly.

Is there some other way to try 10 while keeping 8.1 available till I decide one way or the other?

Thanks again.

 

[ussnorway]

Yes, yes and yes... make a bootable backup image (of before GWX starts to nag) using a good back up program like Acronis or one of the free (not just the default Windows tool) options.

 

[maybe]

Thank you. I appreciate your time.

 

[Ralph Bromley]

You could triple boot, using linux as your third OS as it comes packaged with GRUB a boot loader.
Like make a 8 gig partition for linux using it only for your booting purpases

 

[maybe]

You could triple boot, using linux as your third OS as it comes packaged with GRUB a boot loader.
Like make a 8 gig partition for linux using it only for your booting purpases

I had thought of using Linux grub but how does that solve the problem that the upgrade to W10 uses the same license key as the underlying W8.1?
I'm not worried about the "legalities" since in a dual or triple boot I would only be using one Windows version at a time.

Could you please give me details on how to do this? (PM if necessary) . Would be greatly appreciated by a lot of people.

Which Linux, how, etc.?

 

[ussnorway]

Just to be clear, Linux (any) has no effect on the windows... the main point (as I see it) is you then have a back up option to get into your system and recover files in the event that Microsoft products don't boot after the upgrade or some other "you know what" hits the fan.