DISKPART - How to Partition GPT disk  

Kari said:

Yes, that is a unique detail in recovery partition, or OEM partition as Windows names it nowadays. If placed in front of system partition C:, when it needs to expand after a certain amount of upgrades, it can't, and therefore a new, second OEM partition is created after the C: partition.

To avoid this, it's recommended to place OEM partition after the C: partition. When it needs to expand, it shrinks C: and takes the additional space it needs. It is the only partition in Windows which can expand backwards.

This is told in tutorial step 2.9:




Kari

Yes, I am afraid I missed that the first time. It is actually cool that the recovery partition can do that, and I am sure there is a very good reason why it does not automatically expand forwards. Thanks for confirming.

I am just starting over again here, and this time I will make my own custom diskpart scripts, using the guide for a template.

About the recovery partition, any reason to be concerned it, like the EFI partition, showed as 100% free in Disk Management?

Also, in the following guide, Microsoft's script recommends assigning the letters S and R to the EFI and Recovery partitions respectively, is it okay that we are leaving that out and only assigning a letter for the Windows partition?

https://docs.microsoft.com/en-us/win...ive-partitions

Kari said:

EFI partition will always be shown as empty. Recovery / OEM partition should not be empty, on my various real and virtual machines it shows between 10% and 25% used. Did you set the partition ID correctly?




EFI and Recovery / OEM partition do not need drive letters. Instead, I use letter R for my custom recovery partition: Factory recovery - Create a Custom Recovery Partition | Tutorials

Kari

I used the following custom script, created using script 1 from this thread:

Code:

rem DISKPART script for single 230GB disk dual boot
rem ---------------------------------------------------
rem Select Disk, wipe it empty, convert to GPT
rem 
select disk 0
clean
convert gpt
rem
rem ---------------------------------------------------
rem Create & format 600 MB EFI System partition 
rem 
create partition efi size=600
format quick fs=fat32 label="System"
rem
rem ---------------------------------------------------
rem Create 16 MB MSR partition (will not be formatted)
rem 
create partition msr size=16
rem
rem ---------------------------------------------------
rem Create a 100 GB (1024,00 MB) partition for primary OS
rem 
create partition primary size=102400
rem
rem ---------------------------------------------------
rem Format OS partition, label it, assign drive letter
rem W. Windows Setup will change this drive letter to C
rem when installed. It's important now to use a not
rem reserved letter, therefore we use a letter from
rem end of alphabet
rem 
format quick fs=ntfs label="windows"
assign letter="W"
rem
rem ---------------------------------------------------
rem Create & format a 450 MB recovery partition.
rem Notice that ID must be set exactly as shown! 
rem 
create partition primary size=450
format quick fs=ntfs label="WinRE"
set id="de94bba4-06d1-4d40-a16a-bfd50179d6ac"
rem
rem ---------------------------------------------------
rem Exit Diskpart 
rem 
exit

The image in 6.1 also shows that recovery was 100% free is Disk Management?

What can I do? I am just installing updates again, if there is anyway I can avoid having to start over I would appreciate it!

Please note, I am using Windows 10 install media I created several years ago with Rufus.

Kari said:

My apologies, I should have told that the OEM / recovery partition will in most cases be shown empty until the first feature upgrade. No worries, your partition ID is correct.

Thank you Sir, what a relief!

I was staring at Windows update here, which is at 70% of preparing to install 1803, and hoping very much that either one of the updates will populate recovery, or perhaps Disk Management just did not see files that really are there! :)