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I am new to Ubuntu. How can I clean Install Ubuntu to a Laptop without a CD Rom and if I put ISO file in a Flashdrive how it works when booting up?
You can use UNetbootin. Download it, make sure you have no external USB drives plugged in except the one you want to use for installing Ubuntu, and launch UNetbootin.
Select Ubuntu, the version of Ubuntu you want (select
You then can boot from that USB drive and then you can try or install Ubuntu!