(1) Your MSR partition is 128 MB. Its offset on the disk (where it begins) is 17 KB...
Partition ### Type Size Offset
------------- ------------ -------- -------
Partition 1 Reserved 128 MB 17 KB
It's best to let it alone. In a clean install that is a UEFI install onto a GPT disk, that partition will immediately precede the Windows partition. (I think a Legacy install onto an MBR disk has no MSR partition.)
And these days it will be a tiny 16 MB in size. But my computer came with Win 8.1 (like yours) & also had the MSR located elsewhere (actually after C:).
Although Windows system image backup & restore does not show the MSR in any window -- it actually is included in the image into the C: partition, & it is separated out during a restore. Yeah,
it's safest to have Acronis include it in its image. The MSR is visible in DiskPart & many 3rd-party tools, but it can only be deduced to exist in Disk Management.
(2) I'm glad to see you've brought partition 5 back down to a reasonable size. Your recent upgrade to 2004 was supposed to put the Recovery Environment (WinRE.wim file) into there. Then click any
Power button, hold the Shift key, & click Restart would reboot to the Recovery Environment at the "Choose an Option" screen.
But you've got that Push Button thing, & I don't know what's going on...
(a) Did the 2004 upgrade put a WinRE.wim into partition 5?
(b) Did it put one into partition 6 instead?
(c) What version of Install.esd (or Install.wim) is in partition 6?
I think we will find it is version 8.1. Then -- you should delete partition 6 & use your own system images instead. I think you never will want to go back to Win 8.1. Also, we need to determine whether there is a WinRE.wim in partition 5...
Type CMD into Search, & click "Run as administrator", then enter...
DiskPart
Select Disk 0
Select Part 5
Assign Letter=R
Exit
DIR R:\WinRE.wim /a /s
DiskPart
Select Disk 0
Select Part 5
Remove Letter=R
Exit
Show us the output. If it's there, maybe its size & date will say what version it is. Or -- if/when possible -- we'll boot to it (Shift+Restart), then click "Troubleshoot > Advanced Options > Command Prompt". The version
of the Command Prompt is close enough to the version of the Recovery Environment...

But right now, ReagentC is saying Shift+Restart goes to partition 6. (I know how to set it for partition 5, if there is a WinRE.wim in it.)
(3) Those commands needed to be done at an Administrator Command Prompt: Type CMDinto Search, & click "Run as administrator". You were at a PowerShell (PS) prompt. Here is an illustration of what I meant.
I plugged in my Win 10 Installation USB drive, & it got letter E:. I did a search for
Install.esd beginning in E:. /a means find it no matter what the attributes. /s means search the specified directory (E:) & all sub-directories.
Microsoft Windows [Version 10.0.19041.388]
(c) 2020 Microsoft Corporation. All rights reserved.
C:\WINDOWS\system32>DIR E:\Install.esd /a /s
Volume in drive E is ESD-USB2004
Volume Serial Number is 1E0E-16D3
Directory of E:\sources <<< There is the Directory
07/03/2020 09:53 PM 3,482,988,958 install.esd <<<There is the file
1 File(s) 3,482,988,958 bytes
Total Files Listed:
1 File(s) 3,482,988,958 bytes
0 Dir(s) 11,435,892,736 bytes free
So, I put "E:\Sources\Install.esd" into the DISM command. You will have to do it before removing your letter R: from the Recovery partition.
C:\WINDOWS\system32>DISM /Get-WimInfo /WimFile:E:\Sources\Install.esd /Index:1
Deployment Image Servicing and Management tool
Version: 10.0.19041.329
Details for image : E:\Sources\Install.esd
Index : 1
Name : Windows 10 Home
Description : Windows 10 Home
Size : 14,212,376,596 bytes
WIM Bootable : No
Architecture : x64
Hal : <undefined>
Version : 10.0.19041 <<< That's Win 10, version 2004
ServicePack Build : 264
ServicePack Level : 0
Edition : Core
Installation : Client
ProductType : WinNT
ProductSuite : Terminal Server
System Root : WINDOWS
Directories : 20255
Files : 87841
Created : 5/11/2020 - 1:49:13 AM
Modified : 7/3/2020 - 9:52:37 PM
Languages :
en-US (Default)
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