The System Reserved partition is fine at 100 MB,
a
combined System Reserved with Windows RE should be a minimum of 300 MB (per Technet)
If you want to just try the Win10 install again - that might be the most expedient. If you want the machine to be 'technically correct' then go through the process below.
Rather than ask you to go through a bunch of disk schema gyrations (shrink, resize, create extended.create logical, move Windows....), I'll agree with Mystere and suggest that you 'grow' the System Reserve part (labeled Data on Disk 1) to 450 MB.
Keep in mind throughout this exercise that everything is MEGABYTES - I screw that up sometimes - too conditioned I guess.
This takes a bit of work, but it's not difficult. Read through this and ask any questions, once you boot to PW, you'll be incommunicado (unless you have another means to get to the forum which would be great!)
Download Minitool Partition Wizard and put it in on a bootable disc or USB flash drive.
Scroll down, 2nd from the bottom is Partition Wizard Bootable CD
Free Edition
Click on the blue download button.
Attachment 20642
This page details putting the ISO to disc or USB drive:
This page describes the resize / mover operations you will perform:
The first thing you have to do is shrink C: - shrink it by 350 MB (your system reserve is already 100 MB, so when you're finished it will be 450 MB)
Selet C:
then select move/resize .. the fields are self explanatory - all you have to do is the math (current size - 350 MB)
set 0 MB after the drive to move it. The graphical interface gives you visual confirmation - you should see 350 MB of free space to the left of C:
PW takes a bit of getting used to operationally. First you tell it what you want to do, then you have to confirm the operation by pressing Apply.
Once you're sure you have it right, hit the Apply
There are two places you can confirm / apply (one is on the left operation pane OR there's also a main button up top)
Half way there....all you have to do now is extend System Reserve (labeled Data)
Select Data
select the move/resize operation
use the slider to consume all of the free space (the 350 you made available in the previous operation)
Once you're sure you have it right, hit the Apply
The partiton should now be 450 MB
Might as well change the labels to avoid any confusion in the future.
Change the volume label
System Reserve on Disk 0 to HDD reserve (or anything that makes sense to you)
Change the volume label
Data on Disk 1 to System Reserve
Restart your machine and see if Win10 installs.
Thanks