The PPA source for unetbootin in the accepted answer includes the prefix to disable shared memory access in the default run command so that launching it from the GUI shortcut just works without any hassle: gezakovacs/+archive/ubuntu/ppa
unetbootin exe download
The people here are advising against its use because it's known to break some live systems.
And for all the distributions you just listed, writing the images to a USB drive with `dd` works fine, so there is no need to use unetbootin there.
This is a very odd thread. By all means suggest alternatives to unetbootin. I don't use it and certainly never will. But when suggesting alternatives takes on the flavor of suggesting that the OP shouldn't care that the unetbootin program doesn't run properly it has gone too far. Unetbootin is actively maintained in the [community] repo. If the program does not run as intended, it is a bug that warrants fixing. And if the OP's problem and workaround is reproducible by others, then this should be filed as a bug on the bugtracker as the allegedly-problematic shell script is distributed with the arch package and not from upstream.
Trilby's post made me realise that I have overread the "multi-boot" part (I think this is where OP wants to go). Yes, unetbootin itself is not broken - it just doesn't work very well for at least Arch Linux.
I'm not sure how this translates to Linux (I'm sure it's somehow applicable, I'm just not sure how it translates exactly), but I was having the same problem on Mac, and I believe it was because of how I'd formatted my USB stick. Originally I had just created a partition as FAT and was able to load many different ISOs onto the device. Then I made a mistake and had to re-format(?) the whole device, which included re-making the file/partition table. Originally I just chose the default "Scheme", "GUID Partition Map". From this point on I was having trouble. I had a hunch that it might require the "Master Boot Record" scheme, so I erased the whole USB stick again with that setting. Then when I ran unetbootin again it worked without issue.
there is a good solution that I always use since unetbootin does not always work. It is the command line tool called dd. This is how to use it to write a bootable iso on a usb key: go to the folder where you downloaded the iso, open a terminal and type: dd if=name_of_the_iso of=/dev/sdx [replace x with the letter of your drive. If you do not know it, type the command df -h and look for your drive] bs= 2MB && sync
So it goes like this:
dd if=path_to_the_iso of=path_of_the_drive bs=2MB && sync
When the terminal prompt comes back, that means that the key is ready to use.
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