Windows 10: Loss of MBR .. A Story

I have two PCs. One which I'm using now, and another, older, that is a 'guest' user, and back-up. Each has been updated with W10 v 1903. Now, as they used to say on radio: The rest of the story ..

My main machine had a 500GB SEAGATE HDD. I purchased a 1TB SEAGATE to replace this, as I needed more operating space. I 'cloned' the 500GB to the 1TB, successfully using SEAGATE disc wizard. Both of the disks were capable of booting up and driving my machine.

My 'guest' has a 300GB Western Digital HD, so I decided that I would take the 500GB, transfer it to the guest machine, and expand that capability. I removed the 500GB from the main machine, and transferred it to guest. Still using the 300GB HD, I booted up, and used disk management to ascertain that both disks were active, and that both had MBR's. The disk management showed that both disks were as required. I closed down the machine, unplugged the 300GB drive, and rebooted.

Came up with BLUE SCREEN; and the note that "Something has happened to your PC during the boot process to …[you know the rest]" The machine then re-started on it's own - this time instead of the BLUE SCREEN I got the digital text screen that shows the individual processes during boot up. After running through DHCP the machine stopped and told me [in essence] YOU HAVE NO MBR on this disk.

OK, so I shut down the machine; plugged the 300GB back in, and started up; no problem. I opened disk management: DISK 0 [300GB] has MBR, disk 1 [500GB] has only ACTIVE disk, no MBR.

Where did the MBR GO?

Thinking this may be only the guest problem I took the 500GB back to my main machine, and go the same results. OK, so I'll re-clone the disk and see what happens. Same scenario. I've used EASEUs, and SEAGATE to attempt to re-instate MBR on the disk in separate partitions, the partitions show on the disk, but only has an MBR on it when I leave it in the main machine.

DOES ANY ONE have any ideas on why this is happening? I've been working with computers and programs since '64, and this one has me completely bamboozled! Any help would be greatfully accepted, as I'd like to get to the bottom of this.

Ativar

:)

 

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.

 

Convert only one partition on the disk from MBR to GPT

Step 2
Convert MBR to GPT without data loss

 

Convert MBR to GPT without data loss?

You can use AOEMI Partition Assistant, a freeware that allows you to
convert MBR to GPT without data loss. If you want to have a 100% security, you can backup your whole disk with the brother product - AOMEI Backupper.