Installation issue

Mostafa Ahemd

New Member
Apr 10, 2019
hello All,

i've tried to setup Proxmox on PC test ,
Dell Optiplex 990 with 16 Gb Ram Cpu Corei7 x64 with VT

and when i try to boot by usb and select Install proxmox ve

it's start setup then give me this error
searching for cdrom
testing again in 5 seconds
unmount : can't unmount /mnt: invalid argument

so please help me

I had a similar issue. Mine was resolved by switching from a usb 3.0 device to a usb 2.0 device. I'm using a dell r710 so its older hardware but thats what resolved it for me.

Edit: Also make sure you are selecting the USB as the boot device.
I encountered these errors on a DELL PE R720xd booting via BIOS (not UEFI).
I used Rufus in Windows to create the USB image from the ISO file. It provides two modes - ISO Image mode and DD Image mode.
ISO Image mode (recommended) failed.
DD Image mode worked.

Try using Rufus with DD Image mode.


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