Windows 7 Install Destroyed???

[smithg97]

So i decided it was about time to wipe all my drives and start fresh installs for Win 7 & Win 10 (using dual boot from the same M.2 SSD).

I managed to get the Win 7 OS more or less back to how i want it and then i noticed that my 4TB HDD had been formatted as MBR rather than GPT so had to uninstall everything that i'd put on this drive and drive to format as GPT. I attempted this by inserting the Windows 7 install disc and formatting the drive that way, i think i may have shot myself in the foot though as i was not able to extend or delete the partitions, only the 100mb system reserved partition. After doing this i tried to boot back into my Win 7 OS and the M.2 SSD that it is installed on is no longer visible in the boot priority options of BIOS 🙁

Please could i ask for help on resurrecting the OS and changing the 4TB HDD to GPT (all data is deleted).

 

[alceryes]

I think you can only install to an MBR disk if your BIOS is in legacy mode and you need legacy mode for your current Windows 7 install so it's preventing the Windows 10 install.
Hmmm, I hate to say this but I think you're only solution will be to reinstall Windows 7 x64 in UEFI mode using GPT for your boot disk. Then try installing Windows 10 x64 in dual boot. Be sure to check out the Windows 10 dual boot guides floating around the internets before you begin.

 

[smithg97]

Yes, i think a reinstall of Windows 7 is now necessary as i accidentally deleted the system reserve partition which contained the boot manager and startup repair doesn't seem to be going anywhere and am unwilling to potentially wait for tens of hours when it still may not resolve the issue 🙁

My BIOS default settings are "UEFI & Legacy" mode so i don't have any issues installing an OS to MBR format drive, the problem i have is that when i attempted the Win 7 reinstall i stupidly formatted my 4TB drive as MBR rather than GPT and when i load the Window Pre-installer and select custom install am i not able to delete the partitions on this drive. So am not sure whether a fresh Win 7 install will allow me to re-consolidate this drive using diskmgmt.msc and then convert to GPT and then partition once again, any ideas?

I will attempt a reinstall of Win 7 later and carefully ensure that i format the 4TB HDD in the right way (e.g. GPT) as this whole process has been ridiculously painful! Especially as i'm going to have to phone Microsoft again for the 2nd time this week to request that they allow me to reactivate my Office 2013 applications.

 

[alceryes]

Try installing Windows 7 using GPT (in UEFI mode) may help with the dual boot setup. There's no downsides to it as GPT is better in all aspects.
Also, before you spend hours installing programs and customizing your Windows 7, get Windows 10 at least installed and accessible. That way you know all the Windows 7 work won't be wasted.

 

[smithg97]

Just to clarify, the drive that i need to convert to GPT (the 4TB drive) is not the drive that i will install the OS to, i will install Win 7 & Win 10 to my M.2 which i will partition into a 50/50 split.

If when i format all my drives again i am unable to delete the partitions on my 4TB HDD do you know of any way to consolidate the drive and the convert to GPT and then partition again? When i select the optical drive as boot priority should i choose the UEFI variant or just the normal DVD option?

 

[alceryes]

You should be able to convert a non-boot drive to GPT from disk management.
Try UEFI for everything. Instead of installing from optical use a USB.