Windows 10: Disk mirror failed; how to reactivate?

Windows 10 1909, x64, running on an old desktop.

I have a microsoft-based mirror of a data drive running, & I noticed that one of the pair of drives dropped.

I determined which one it was and proved it by powering it off. Bought new drive, tested, & replaced new

drive for the one that had failed.


I don't see how to re-establish the mirror in diskmgmt.msc. The 2 disks are there. Almost all the options on the

good drive are greyed out; the only things I see on the disk left hand button are offline/properties/help, all the ones

pertaining to mirroring are greyd out. The right hand button or bar showing the disk space only has format, volume,

reactivate volume &c, not useful.


Same is true for the new disk drive.


Is it the case that I can only do this from a Basic disk? I certainly don't want to delete all the data on the surviving disk in order to go back to a Basic disk to set up mirroring. There must be a better way.


Thanks, ==mwh

:)

 

Disk mirror failed redundancy: Remove mirror or reactivate volume?

Hi,



Thank you for writing to Microsoft Community Forums.



The cause for Failed Redundancy would be that half, but not both halves, of a mirrored volume was imported. In Disk Management, the imported half of the mirrored volume receives Failed Redundancy status, while the disk that holds the
half of the mirror that was not imported receives Missing status. You can import the Missing disk at a later time to restore redundancy.



The solution for Failed Redundancy is to move all disks that span this volume to the new computer at the same time, and then import all of the disks together.



The complete solution is giving in the section A mirrored volume's status is Data Not Redundant from
Troubleshooting Disk Management.



You may also refer the section A dynamic disk's status is Offline or Missing from the above article and try the troubleshooting steps.



If you are still facing any issues related to Mirroring, then I suggest you to post your query in
IT Pro TechNet forums, where we have support professionals who are well equipped with the knowledge on Hard Disk Mirroring.



Hope it helps.



Let us know if you got the help you needed by clicking Yes or No.

 

Disk mirror failed redundancy: Remove mirror or reactivate volume?

Situation:

Windows 10 1803 computer. OS drive is fine. Have two other very large disks ("3" and "4"), mirrored from within Windows. "4" has problem, taking it offline and losing its data (now shows up as "Missing").

Currently we're able to read data from disk #3. Disk Management shows the two disks from the original mirror, both with failed redundancy:





If I right-click on either of them, several options are presented...

"Break Mirrored Volume..." is greyed out, so can't do that.

"Remove Mirror..." is available.

"Reactivate Volume" is available.

Since only disk 3 actually has data on it, we want to preserve it. However, there is too much data for us to backup reasonably; whatever solution we try must not destroy that information.

If we selected "Remove Mirror..." we get this dialogue box:





In our opinion, the text in the dialogue box is not clear. If we run the "Remove Mirror," which drive do we select in order to retain our data? Is the selected drive the one which has its data gone (removed, deleted, toast), OR is that the drive which
has its mirrored data removed (which would be the other drive?

Or... maybe we select "Reactivate Volume"? Does that reactivate the mirrored volume or the specific disk which is selected when reactivation is selected? (as in drive "3" or "Missing"). How do we know which drive's data is considered
the "good" data, which will be mirrored to the other drive? Would be bad to have the non-data from the "Missing" drive to be copied over the real data on drive "3."

Have done a bunch of searching, but haven't found adequate answers.

 

Reactivate Mirrored Volume Windows 10

I recently had a Windows 8.1 install that was upgraded from Windows 7. I had my boot on an SSD and 2 HDD in raid 1 that were functional (through Disk Management). I had a boot (SSD) failure. Using a replacement SSD I mistakenly installed Windows 8 (upgrade
key) because of this I could not activate and upgrade to 10. I had, however, reactivated my mirrored HDD's and re-synced them successfully in Windows 8.1 before learning of my inability to upgrade to 10.

Since then I did a fresh install of win 7 and updated to windows 10. Once in 10, I attempted to reactivate and sync my mirrored HDD's. They both show as failed and when choosing reactivate disk, after 3 seconds, nothing happens. I have not tried reinstalling
7, syncing them then upgrading, but may try that next. In the meantime, is there a way to reactivate the volume or break the volume keeping data intact and simply creating a new mirrored volume? Thanks for the help. I thought I was saving myself trouble
by mirroring instead of keeping them both basic and updating them manually but this may not be the case.