I am new to the Linux OS. Following this tutorial I was able to successfully install VirtualBox-6.1.12 boot it directly from my windows 10 computer and then Ubuntu-20.04.1, and I used the Ubuntu successfully in following tutorials in a linux-based training I am undergoing. I did not install or launch any item from an external device such as a pen drive, CD or DVD. At some point the Linux machine became so slow and I decided to uninstall and reinstall the VirtualBox (from Windows 10 control panel) and follow the tutorial again to reinstall Ubuntu on the VirtualBox. After several attempts, this second process reinstallation of Ubuntu stops at various levels of the tutorial and without success.
In one of the stages where it stops, for example during the execution of step 21 of the tutorial, an unmodifiable form appears in whose fields I can type in nothing
In cases, where I go pass stage 21, I get the error message
This last point is the furthest I have gotten since the start of my attempts to reinstall.
Can someone please hint me?
dmesg |grep squashfs
which should only show the program version message(s), but also highlights errors which only occur on bad media or invalid/corrupted ISO. Also note if you have insufficient RAM in your VM, you can cause squashfs errors too; so check you've allocated the VM enough ram.