MSR Size Curiosity - GPT secondary disks

TV2 said:

The supplemental question is: To delete or to leave alone!

Even at 128MB it's hardly worth recovering the space. I'd leave it be, only deleting it if it gets in the way of expanding an existing partition.

storageman said:

Yes - I noticed that also. But question is what happens when you need to have 15 partitions on that drive ? I always assumed that the reason for the 16mb MSR partition is that the original partition table area is not large enough to handle more than the MBR maximum # of partitions, so I assume a link is placed in the original Partition table pointing at the 16mb MSR partition.

That may be the reason to have an MSR partition. But some time ago, I read another (somewhat vague) explanation: In a MBR disk, and under "some circumstances" (for ex related to RAID), Windows may write info to an area that is not in any partition. This is not allowed in GPT disks, so the purpose of MSR is that that kind of info be written to the MSR.

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Megahertz said:

A MSR partition should be only on the Win 10 drive. All other drives (data drives) should have no MSR partition.

I don´t think so. When a disk is initialized as GPT, an MSR is always created in it. All my external data disks have MSRs.

"A MSR partition should be only on the Win 10 drive. All other drives (data drives) should have no MSR partition."

None of my GPT data drives has a MSR partition. And they are created using Disk Manager from one and only one unallocated space.
Last month I installed win 10 Pro 1909 on a GPT SSD (did created a 16M MSR partition) and during installation I entered audit mode. Attached a 500G HDD, deleted all partitions and created a new one (D: - GPT) using Disk Manager. No MSR partition was created. Then I ran syprep script to move C:\Users (SSD) to D\users (HDD).
Does anyone has an explanation?

TV2 said:

Is this your opinion, or did you read this somewhere? Source please.
It's my opinion as none of my data GPT disks has the MSR partition

It sounds like you did an advanced installation procedure, and something in the way you sequenced the tasks bypassed the creation of a MSR. In my case this was a standard process on creating partitions on a bare drive using default settings.

I've created many GPT data drives using Disk Manager from one and only one unallocated space and none of them has a MSR partition. I think that Disk manager is the basic procedure, not advanced.

Megahertz said:

"Last month I installed win 10 Pro 1909 on a GPT SSD (did created a 16M MSR partition) and during installation I entered audit mode. Attached a 500G HDD, deleted all partitions and created a new one (D: - GPT) using Disk Manager. No MSR partition was created...
Does anyone has an explanation?

Perhaps due to being in audit mode? I have just wiped an external HDD with the Diskpart CLEAN command. Just initialising it to GPT using Disk Management was enough to create a 16MB MSR partition.

If I remember well, on Windows 7, MSR was used to hold the decryption files.
As I see,storageman, TV2 and Bree has Win 10 pro. Do you have the main drive encrypted?