After I posted that response in #7, I went to check your Motherboard Specs etc from MSI website.
I then recked your current BIOS . It is shown in one of the images as
Build date 02-14-2017
Then I noted this about a newer BIOS
Z270 GAMING PLUS (MS-7A75) V1.3 BIOS Release
2017-08-03
I was wondering why they had to release so soon after your BIOS date > I found the following :
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1. This is AMI BIOS release
2. This BIOS fixes the following problem of the previous version:
- Updated micro code.
-
Improved USB 2.0 device compatibility.
- Improved memory compatibility.
- Support clear optane setting.
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That prompted me to test a new
ADATA USB 3.0 Flash disk 32GB as a HighSierra 10.13.2 installer disk in my System with
GA B85M-DS3h +intel i3 4160+Nvidia GT 710 .
I had no problem to reach the Installer screen >Disk Utility. I did not go through a new installation as I already have High Sierra 10.13.2 in that system.
I can then say it is NOT a 32 GB USB that is causing the problem.
- I will suggest upgrading your BIOS which supposedly "improves USB 2.0 device compatibility" according to the manufacturer of this board.
I did not check further as to what problems reported by users prompted them to come up with this new BIOS release.