How to boot to a Ubuntu Live USB, in “Try Ubuntu” mode while Ubuntu is installed in my Laptop?

I want to assign unallocated space to Ubuntu partition and following this.

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I installed Ubuntu by USB, and now I cannot find Try Ubuntu mode, when start my laptop, with USB containing Ubuntu I installed before, just 4 choices allowed:

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Where I can open "try Ubuntu" mode now? Thank you so much!

I used Rufus to install to my USB. My Ubuntu Version: 22.04, and when USB is plugged in, this is I found in Ubuntu Home:

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Update: I try to follow the comment, and find this:

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And when I boot USB, it fails.

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Is this because this USB (I cannot format this when using window: disk is written protected, but can format with ubuntu, I think). Should I format the USB and install Ubuntu into it again by Window and restart to open Ubuntu live USB?

Asked By: Thành An


You have to boot from the USB drive to re-enter the live environment.

Since your second image shows an option for "UEFI Firmware Settings", I’m assuming you’ve installed in UEFI mode. Most likely, when you installed Ubuntu, the installation process modified your system’s boot order, and put the new installation as the first option with the highest boot priority, meaning it will always boot by default unless you override it.

While it is possible to use your BIOS setup program to manually modify the boot order and make external drives the default, this is a bad practice for security reasons. It is much preferred to only override it on individual bootups, which is done by entering the boot menu during startup (normally by pressing ESC or one of the F-keys – consult your system’s documentation if unsure), which will then list all your drives and allow you to select the USB drive and boot from it.

Answered By: Daniel M.