Error Opening BCD Registry only after converting MBR disk to GPT

x509

New Member
#1
I have been been a happy camper using EasyBCD for probably 3 years now, but I got this error message today for the fist time ONLY after converting an MBR drive to GPT.

I useEasyBCD to multiboot to one of five different Windows 10 Pro 64 partitions on two drives. The main drive, with my "usage" windows partition, is a GPT drive. This drive has one experimental Win 10 partition. The second drive is MBR, and has the 3 remaining Win 10 partitions. Everything ran fine.

This second drive is 1 TB, with lots of wasted space, so I thought I would convert to GPT so I could have more primary partitions. So I used MiniTool Partition Wizard to convert that MBR drive to GPT. (The free version only converts a non-OS drive.) The conversion ran fine, but then EasyBCD couldn't find the partitions on this second drive. So I ran bcdboot X:/windows /s X: for each partition. At this point, EasyBCD displayed a window with this Error Opening BCD Registry at the top of the window, and no way to close the window. I had to use Task Manager to stop EasyBCD.

So I ran MiniTool again to convert the drive back to MBR, and re-assigned drive letters to each of the 3 Windows partitions. Normally, for security, I unassign a drive letter to these other partitions so my "usage" Windows doesn't get confused. Once I assigned this drive letters, EasyBCD ran fine. Then, for for security, I unassigned those drive letters. Now EasyBCD throws up the error window again. I don't understand why, because until today, I always ran with drive letters unassigned, and EasyBCD managed fine.

So what happened with this new error message, and what should I do? I'm OK with running bcdboot command lines.

Also, any idea why I got these error messages in the first place when I did the conversion to GPT?

x509
 

Terry60

Knows where his towel is.
Staff member
#2
Now EasyBCD throws up the error window again.
Do you mean bootmgr ?
EasyBCD takes no part in the actual booting of your PC - or are you saying you can't run EasyBCD without assigned disk letters ?
 
#3
Terry,

Now, I can't even run EasyBCD without assigned disk letters. Before I went through that change from MBR to GPT and then back again to MBR, I was able to run EasyBCD without assigned disk letters.
 

Terry60

Knows where his towel is.
Staff member
#4
If you can't run EasyBCD without assigned disk letters, that implies it's looking for the BCD on one of those drives.
When you're up and running, which drive is flagged "system" in Disk Management.

Disk Management flags have the following meanings
"boot" = "this is the system you're running"
"system" = "this is where I found the boot files for the currently running system"
"active" (on the first HDD in the BIOS boot sequence) = "this is where I started the search for the boot files"
"active" (on subsequent HDDs in the BIOS boot sequence) ="this is where I will look if I don't find something in the MBR on the first HDD"

If it's not one of the drives in question, check EasyBCD > Tools > Options to make sure you're not "automatically load....."ing a BCD instead of the "live" one