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Windows 7: Cant convert to MBR because of this (100MB EFI System Partition)

22 Jun 2015   #1
RvB Vakama

Windows 7 Home Premium SP1 64-Bit
 
 
Cant convert to MBR because of this (100MB EFI System Partition)

Hey guys, thank for any help you are able to supply...

So I corrupted my windows 7 boot files when reinstall an antivirus and turned off my pc half way through install, anyway im trying to convert my gpt style ssd partition to a mbr so i can reinstall windows 7 on it. because for some reason i cannot install it on a gpt style. i have looked at so many guides on how to convert it and they would work if i did not have this silly 100MB EFI System Partition (see image attached). I want to just have my ssd Completely formatted to NTFS 4k allocation size MBR please.

also i tried deleting the partition with diskpart in cmd, but it just stops responding and crashes.

thanks for any help!




Attached Thumbnails
Cant convert to MBR because of this (100MB EFI System Partition)-cant-delete.png  
My System SpecsSystem Spec
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22 Jun 2015   #2
whs
Microsoft MVP

Vista, Windows7, Mint Mate, Zorin, Windows 8
 
 

With the bootable CD of Partition Wizard you should be able to do it:

Bootable Partition Manger | MiniTool Partition Wizard Bootable Edition
My System SpecsSystem Spec
22 Jun 2015   #3
GokAy

Windows 7 Ultimate x64 SP1
 
 

Since you have EFI BIOS, I guess you need to disable secure boot in BIOS to install windows 7?
My System SpecsSystem Spec
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22 Jun 2015   #4
RvB Vakama

Windows 7 Home Premium SP1 64-Bit
 
 
Nope

Quote   Quote: Originally Posted by whs View Post
With the bootable CD of Partition Wizard you should be able to do it:

Bootable Partition Manger | MiniTool Partition Wizard Bootable Edition
Nope it gives me a message that windows 7 cannot be installed because the style is GPT, I can format it but the 100MB wont go away it is just left alone when any formatting is taking place
My System SpecsSystem Spec
22 Jun 2015   #5
RvB Vakama

Windows 7 Home Premium SP1 64-Bit
 
 

Quote   Quote: Originally Posted by GokAy View Post
Since you have EFI BIOS, I guess you need to disable secure boot in BIOS to install windows 7?
the drive that I want to reinstall on Had broken windows 7 which has since been formatted (E:\), the current working windows 7 I am using to post this is on my 2TB SSHD (C:\) why would turning off secure boot change anything on the formatted drive (E:\)
My System SpecsSystem Spec
22 Jun 2015   #6
TVeblen

Microsoft Community Contributor Award Recipient

Windows 7 64 Bit Home Premium SP1
 
 

A couple of things come to mind that you should check:

You show 2 disks: Disk 0 is the problem disk. Disk 1 contains a Windows installation - you don't say what version of Windows is installed there. You should.

On an UEFI BIOS system, if you have any GPT formatted disks in the system then Windows 7 must be installed on a GPT disk. Any data drives can be either format (MBR or GPT), but the OS must be installed on a GPT disk in a mixed disk system. So we need to know if Disk 1 is a GPT disk also.

Since you already have an OS installed in your system (on Disk 1) it may be that it is using the EFI System partition on Disk 0, if Disk 0 was installed at the time the OS was installed on Disk 1. A quick test for that would be to disconnect Disk 0 and see if the OS on Disk 1 starts up.

To install Windows 7 on a GPT disk in a system that has a UEFI BIOS you must boot the install media in UEFI mode, usually using the Boot Menu and selecting the version from there. This is sometimes not possible when using the install DVD in some systems. In these cases you could create an install USB stick to make the installation in UEFI mode.
UEFI Bootable USB Flash Drive - Create in Windows
My System SpecsSystem Spec
22 Jun 2015   #7
RvB Vakama

Windows 7 Home Premium SP1 64-Bit
 
 

Quote   Quote: Originally Posted by TVeblen View Post
A couple of things come to mind that you should check:

You show 2 disks: Disk 0 is the problem disk. Disk 1 contains a Windows installation - you don't say what version of Windows is installed there. You should.

On an UEFI BIOS system, if you have any GPT formatted disks in the system then Windows 7 must be installed on a GPT disk. Any data drives can be either format (MBR or GPT), but the OS must be installed on a GPT disk in a mixed disk system. So we need to know if Disk 1 is a GPT disk also.

Since you already have an OS installed in your system (on Disk 1) it may be that it is using the EFI System partition on Disk 0, if Disk 0 was installed at the time the OS was installed on Disk 1. A quick test for that would be to disconnect Disk 0 and see if the OS on Disk 1 starts up.

To install Windows 7 on a GPT disk in a system that has a UEFI BIOS you must boot the install media in UEFI mode, usually using the Boot Menu and selecting the version from there. This is sometimes not possible when using the install DVD in some systems. In these cases you could create an install USB stick to make the installation in UEFI mode.
UEFI Bootable USB Flash Drive - Create in Windows
are you saying that my windows 7 on disk 1 could be relying on the 100MB files on disk 0, i did not think that was possible in any case, plus when i installed windows 7 on disk 1 i did not have any other disk plugged in, so it cant be relying on the 100MB from disk 0. Also disk 1 is not gpt because when i list details in diskpark in cmd it says its not gpt.

PS this UEFI BIOS and all the other terminology you are using confuses me, how can i figure out if my pc matches what you are saying?


Attached Images
Cant convert to MBR because of this (100MB EFI System Partition)-cant-delete-cmd.png 
My System SpecsSystem Spec
22 Jun 2015   #8
TVeblen

Microsoft Community Contributor Award Recipient

Windows 7 64 Bit Home Premium SP1
 
 

If you installed Windows 7 without any other disks attached then that should eliminate the EFI Partition possibility.
Just do a quick test: disconnect the power from Disk 0 and then see if Windows starts from Disk 1.

UEFI BIOS: When you go into your BIOS settings, can you use your mouse, or is it the legacy BIOS that could only use keyboard?
The new UEFI BIOS can use mouse control.
My System SpecsSystem Spec
22 Jun 2015   #9
RvB Vakama

Windows 7 Home Premium SP1 64-Bit
 
 
I'm silly

Quote   Quote: Originally Posted by TVeblen View Post
If you installed Windows 7 without any other disks attached then that should eliminate the EFI Partition possibility.
Just do a quick test: disconnect the power from Disk 0 and then see if Windows starts from Disk 1.

UEFI BIOS: When you go into your BIOS settings, can you use your mouse, or is it the legacy BIOS that could only use keyboard?
The new UEFI BIOS can use mouse control.
ok i will try to disconnect disk 0 and boot, just to see if disk 1 is really not depending on disk 0
and my bois had keyboard and mouse control, i actually got the bot right here. wow im pretty dumb the box said like everything i need to know about my bois and motherboard (see image)


Attached Thumbnails
Cant convert to MBR because of this (100MB EFI System Partition)-im-dumb.jpg  
My System SpecsSystem Spec
22 Jun 2015   #10
TVeblen

Microsoft Community Contributor Award Recipient

Windows 7 64 Bit Home Premium SP1
 
 

We've all been there once!
My System SpecsSystem Spec
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 Cant convert to MBR because of this (100MB EFI System Partition)




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