sdb1 mount problem

[Emroy]

Hello,

I recently bought a secondhand dell laptop with second gen i3 cpu, 8gb of ram and 240 gb ssd. The laptop doesn't have any other physical drives (no cd/dvd drive, no hdd)

I installed kubuntu 17.04 without a problem and have been using it for about a week now.

Yesterday though, I tried formatting a usb using KDE partition manager, to create a bootable USB for another pc.
First I deleted all the partitions inside the USB and created a new fat32 partition.
Then, because I was unable to mount the USB after the format, I tried setting the mount point to /media/<username> and then mounted from command line using:
mount /dev/sdc1 /media/<username>
Which allowed me to create a bootable USB using unetbootin.

After restarting, I tried to boot from my USB to see if it works properly.
The USB did not work work, but more importantly, after that I have been unable to boot kubuntu. It always pops up in emergency mode.

I am pretty sure the USB has something to do with it.
First, if I don't have the USB plugged in, emergency mode pops up after a timeout in sdb1.
Second, even though my USB was seen as /dev/sdc on the partition manager, in emergency mode it is /dev/sdb.

During kubuntu installation on this laptop, I picked the default partitioning of the installer. I cannot imagine what /dev/sdb was previously.

I also tried editing /etc/fstab, but it didn't help. Bellow you can see it's contents before I do anything with it.
UUID=e3238d9f-... / ext4 errors=remount-ro 0 1
/dev/sdb1 /media/<username> fat32 defaults 0 0

I've spent a whole day on this to no avail. Please, someone help me!

[vinnywright]

remove the edit to fstab ,,,, /dev/sdb1 /media/<username> fat32 defaults 0 0

VINNY

[GreyGeek]

What Vinny said, AND, don't use /dev/sdX in fstab. Use UUID's instead. A storage device can switch /dev/sdX locations when you mount another one. For example, I had two 750Gb HD's in my laptop. While they both were mounted in fstab using UUID's, I could also mount them using "sudo mount /dev/sda1 /mnt", for example. Then I took out my CDROM and replaced it with an HD Caddy and plugged another 750Gb HD into that caddy. Instead of becoming /dev/sdc, it became /dev/sdb instead, and what was /dev/sdb became /dev/sdc. Now, I can manually mount /dev/sb1 to /backup, which I often to in order to store btrfs snapshots on them, but if i wanted to mount /dev/sdb1 to /backup in fstab I'd use its UUID instead, because UUIDs assigned to a /dev/sdX device never change.

[Emroy]

I have managed to boot properly after removing the line from fstab and executing systemctl reboot. Thank you!

The thing is though that I never did anything to fstab before I encountered the problem.
How did that problematic line get there in the first place?