Windows 10: Accidentally set up an external drive as Master Boot Record - how can I now change this to GPT

Hello -

I've got a 6TB archival drive that on first use I accidentally set up as MBR, I guess meaning I can't access the full capacity, so I need to change this now to GPT - I can't see how to do this - can anyone help?


Thanks in advance!

:)

 

clone MBR HD to bootable GPT partition?

Hi,

1. You cannot convert mbr to gpt without data loss. otherwise, you can follow directions here:

FROM WINDOWS RECOVERY CONSOLE:

To change a master boot record disk into a GUID partition table disk using a command line

• 
  Back up or move the data on the basic master boot record (MBR) disk you want to convert into a GUID partition table (GPT) disk.
  
• 
  Open an elevated command prompt (right-click Command Prompt, and then click Run as Administrator) and type diskpart. If the disk does not contain any partitions or volumes, skip to step 6.
  
• 
  At the DISKPART prompt, type list disk. Make note of the disk number you want to convert.
  
• 
  At the DISKPART prompt, type select disk <disknumber>.
  
• 
  At the DISKPART prompt, type clean.
  

2. I'd suggest converting your vista drive to a virtual machine, load that up on your windows 10 system and use a program like virtualbox to run it.

 

booting an external drive

Hi,

The sector size thing is a possibility that I didn't think of... It shouldn't be a problem, but it could be depending on the machine... I do know that Seagate does something to simulate the 512 sectors on a 4k drive... I'm not sure they do this on Internal
drives, but do on external...

GPT is a newer type disk formatting... actually the "Initializing" part of it...

It allows for more Partitions than the four maximum or the older "MBR" type drive...

It uses a different type of file table to store the file locations on the drive...

If you delete everything on a HDD, then Initialize it again, you will see this as an option... It may be called GUID when Initializing...

A windows installation will not recognize a GPT drive as a boot device if it is using "Legacy" Bios... Which is what everything used until the last few years. More precisely, your Legacy BIOS will not recognize it as a boot device...

Same type of problem with the newer UEFI Bios... It will not recognize a drive formatted\initialized with the older method as a boot device... It specifically looks for a specific partition on a GPT drive...

Both types of drives still use FAT32 and NTFS...

It may not be possible to use the drive as intended, but I wouldn't give up yet...

First off... right click on the Disk 0 or Disk 1 or whatever appropriate for the drive in the lower part of Disk Management and select Properties... Volumes..

Let me know whether it is listed as a "Partition Style" Master Boot Record (MBR) or GUID Partition Table (GPT)... Then we can go from there...

 

dvd/cd ram drive set up as the master boot record (MBR)

My laptop been upgrade to windows 10 pro 64 bit. now when I tried to burn a cd or a dvd music mp3 , it go through the whole steps and at the end when it says that the burning was completed. there is no music on the cd disc, only after a few seconds a message
appears on the screen . "still files awaiting to get burn" lost a lot of cd.

under Disk Management, I see the partition style of the "F" drive (dvd/cd ram drive) set as: MRB (master boot record). how can I change that only my "C" drive is the MRB. (Can I remove "F" drive from my partition

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