Dual boot - Uninstalling windows or mint?

[Cicero86]

Hi,

I have dual booted before but now I have a question;

Here's the situation:
I just got a new machine and I'm planning to have win 7 first (posting from it now) then linux mint and everything is ready for dual boot, I even freed up space on hard drive and made it "unallocated".

But as you may know, Windows is prone to crash often and I need to reinstall a fresh installation of it every now and then.

The question is:

What will happen if I inserted a USB with win on it and tried to format the C Drive to do a clean install. Specifically, what will happen to the boot list?
Will it be messed up?

Has this situation happened to anyone here before?

[michael louwe]

@ Cicero86, .......

.

.
For a multi-boot system on an internal hard-drive, the last OS installed will take over control of the Boot Partition, either the MBR or EFI System(Boot) Partition. But because Windows does not read Linux files, Windows should be installed before Linux.

For a Legacy BIOS mode install, if you need to reinstall Win 10 in a dual-boot system, run the Live LM USB-stick or DVD and just do a
sudo grub-install /dev/sda to restore grub. You can also install and use the Boot Repair tool.
... For a UEFI mode install, the procedure to restore grub-efi after a Win 10 reinstall is more complex. Try installing and using the efibootmgr tool on the Live LM media to restore grub-efi.
... So, best to use Legacy BIOS mode install for a modern UEFI computer, ie by enabling CSM or Legacy BIOS in BIOS setup.

Last resort is to reinstall Win 10 and then also reinstall Linux Mint alongside Windows.

It is recommended to keep the 2 OS on separate drives, eg install LM on an external USB hard-drive, if using a laptop.

[fabien85]

For reference, here is the procedure to reinstall grub in Legacy mode : https://sites.google.com/site/easylinuxtipsproject/grub
and in UEFI mode : https://sites.google.com/site/easylinuxtipsproject/6 (it's more complex as michael said)

[Cicero86]

Thanks all

[UgotME]

Do yourself a big favor and turn off "Fast Startup" in the power options if you're using Win10. It's a check box that is populated by default and causes mounting issues that will ruin an otherwise fun evening of using Linux. You can run fsck until the cows come home and it will tell you everything's fine with your Linux boot. The entire time it's your ex-wife, who you still have to deal with for various reasons, jealous and doing whatever she can to sabotage your new found minty happiness by not letting you mount your drives. I never had this problem until Win10.

[Cicero86]

@ Cicero86, .......

.

.
For a multi-boot system on an internal hard-drive, the last OS installed will take over control of the Boot Partition, either the MBR or EFI System(Boot) Partition. But because Windows does not read Linux files, Windows should be installed before Linux.

For a Legacy BIOS mode install, if you need to reinstall Win 10 in a dual-boot system, run the Live LM USB-stick or DVD and just do a
sudo grub-install /dev/sda to restore grub. You can also install and use the Boot Repair tool.
... For a UEFI mode install, the procedure to restore grub-efi after a Win 10 reinstall is more complex. Try installing and using the efibootmgr tool on the Live LM media to restore grub-efi.
... So, best to use Legacy BIOS mode install for a modern UEFI computer, ie by enabling CSM or Legacy BIOS in BIOS setup.

Last resort is to reinstall Win 10 and then also reinstall Linux Mint alongside Windows.

It is recommended to keep the 2 OS on separate drives, eg install LM on an external USB hard-drive, if using a laptop.

Hi, Michael.

Sorry I'm still wondering and I need to understand better. What will happen if windows 7 crashed while I'm having both win and mint on the machine?

Will I be simply able to install win 7 by the normal procedures of plugging in the win 7 flash drive then installing by formatting C?

I mean, will this procedure erase my linux mint or ruin grub?

I expect that it (the new windows 7 setup) won't be able to read the space I've already dedicated (by then) for mint (so mint should be safe from any "formatting" harm, right?). so it will read the usual drives windows reads (C, D, etc.) and I will have the option of formatting what win understands as C, right?

The thing that I don't know and would like to know if anyone has been through an experience like this and what happened then?

having win7 first, then linux, then needing to re-install win7 again.

sorry I'm not a native speaker so please educate me in simpler English.

I'm trying to read all the links but they don't give me a simple straight answer to my question and it makes me a little bit confused...I hope you don't get annoyed by my question...

[Cicero86]

@ Cicero86, .......

.

.
run the Live LM USB-stick or DVD and just do a
sudo grub-install /dev/sda to restore grub. You can also install and use the Boot Repair tool

Do you mean that LM as a live USB OS can edit the machine's grub without being installed on it? Wow! really?

[Cicero86]

For reference, here is the procedure to reinstall grub in Legacy mode : https://sites.google.com/site/easylinuxtipsproject/grub
and in UEFI mode : https://sites.google.com/site/easylinuxtipsproject/6 (it's more complex as michael said)

fabien85 thanks for the links! this website is very simple yet contains a lot of information about linux (specially for beginners like me hehe)

[Cicero86]

Do yourself a big favor and turn off "Fast Startup" in the power options if you're using Win10. It's a check box that is populated by default and causes mounting issues that will ruin an otherwise fun evening of using Linux. You can run fsck until the cows come home and it will tell you everything's fine with your Linux boot. The entire time it's your ex-wife, who you still have to deal with for various reasons, jealous and doing whatever she can to sabotage your new found minty happiness by not letting you mount your drives. I never had this problem until Win10.

I got U, UgotME Thanks a lot I'll keep that in mind if I installed win10.

The thing is I'm trying to get myself accustomed to linux mint so I can avoid using windows all together. It's getting really annoying. The only thing that's keeping me using win is games. And I'm getting older (busier) by time and I know I won't care for games soon. So I'm "training" myself for linux now! hehe.

[michael louwe]

@ Cicero86, .......

Sorry I'm still wondering and I need to understand better. What will happen if windows 7 crashed while I'm having both win and mint on the machine?

Will I be simply able to install win 7 by the normal procedures of plugging in the win 7 flash drive then installing?

I mean, will this procedure erase my linux mint or what?

.
AFAIK, the initial install of Win 7 would have created a hidden MBR (Master Boot Record) at the beginning of the internal hard-drive with the Win 7 bootloader or Boot Manager installed in the MBR = computer booted straight into Win 7.. Later, when Linux Mint was installed alongside Win 7, the Linux Grub bootloader was also installed in the MBR and took over control of the boot process from Win 7 Boot Manager. Since Linux could read Windows files, you were presented with a Grub menu after startup to boot into either Linux or Win 7.

In the above event as you described, you plug in the Win 7 USB Flashdrive to reinstall Win 7 and you will then be given the option to delete only the faulty previous Win 7 partitions to create a new unallocated space for you to re-partition the unallocated space accordingly for a new install of Win 7, eg to create separate C:\ and D:\ drives in the appropriate size. This should be done without touching the good Linux partitions.
... The reinstall of Win 7 will create a new MBR with the Win 7 Boot Manager in it, ie the Linux Grub bootloader is no longer present in the MBR.

After the reinstall of Win 7 has completed, the computer will boot straight into Win 7, ie Linux can no longer be booted. But because Win 7 does not know how to read Linux files, it is of no use to create a new boot entry for Linux with the Windows EasyBCD program or bcdedit command tool .
... So, the Linux Grub bootloader has to be reinstalled in the MBR, in order to restore the Grub menu and be able to boot both Linux and Win 7.

You can also launch GParted from the Live LM USB/DVD to delete all the faulty Win 7 partitions to create a new free space to accommodate a reinstall of Win 7.