UUID=33bcf4ef-b484-41ec-940b-57a5c18a95ae / ext4 errors=remount-ro 0 1

UUID=199fa164-4299-48d1-9c7d-50da801f2835 none swap sw 0 0

UUID=41d73904-5c69-4831-a7a6-32861ee7d5a8 /media/vitaly/PROJECTS ext4 auto,exec,rw 0 0

UUID=38581832-d6e7-424a-93b9-e193b8402178 /media/vitaly/500 ext4 auto,rw,exec 0 0

UUID=41d73904-5c69-4831-a7a6-32861ee7d5a8 /media/vitaly/BIG ext4 auto,rw,exec 0 0

You can read about fstab here:

https://help.ubuntu.com/community/Fstab

http://ubuntuforums.org/showthread.php?t=283131

https://wiki.archlinux.org/index.php/Fstab

http://www.tuxfiles.org/linuxhelp/fstab.html

http://linux.die.net/man/5/fstab

or man fstab in terminal.

In Lubuntu I have application Disks - maybe you need see to the Mount Options (in More actions... menu). Also - my problem was in Partition Type - I don't know why but I have NTFS, when disk was formatted in ext4. Edit partition type don't erase your data (but backup is always good). And bootable mark need only for bootable drive.

Also - if something not work - try re-order list of mounting disks. I recommend use UUID but not like /dev/sdc1 - because you may have situations when some partition will not auto-mount because you insert USB flash in to computer (and its new device may "capture" /dev/sdc1-name.

If after some changes you can't load your system - Lubuntu (or Ubuntu) may suggest you skip mounting (key F) of problem partition. If you not see screen like this, maybe you will came to the terminal. In terminal:

1) mount -o remount,rw // remount drive for writable access

2) cd /etc // go to etc folder - where we have fstab file

3) vi fstab // open fstab file in vim

4) after edit - Escape and ZZ (after Escape) - save and exit

Ctrl+Alt+Del - reboot your computer.

Remember that if you corrupt you fstab file and can't load your system - you can't edit this file from LiveCD(USB), because your system partition not give you access to write. But maybe you can edit this file from LiveCD, if you find solution (I can't).

Another option for fix fstab - insert HDD in another computer and from another OS fix this (I not try this but I think this will work); or you can install Ubuntu on USB flash (just select flash drive like partition for install - you can install Ubuntu from LiveUSB to another USB - this flash may be your friend in situations like this - when you can't load your system and need to edit some system files or copy your data before reinstall Ubuntu). I prefer eject cable from all my another HDDs when install Ubuntu on flash - for more safety - I don't want edit my boot sector on true system disk.

For example, why this line correct for my system:

[Device] [Mount Point] [File System Type] [Options] [Dump] [Pass]

/dev/sdb1 /media/vitaly/PROJECTS ext4 auto,exec,rw 0 0

1) UUID=41d73904-5c69-4831-a7a6-32861ee7d5a8 partition "name"-hashcode (only partition - not all drive). We want auto-mount this at start-up. Find this UUID in your HDD-manage app.

2) /media/vitaly/PROJECTS - where we will mount, specific folder. Make sure that you have this folder - you need create it. In my case - PROJECTS.

3) ext4 - partition file system. Write our own. You can see it in GPartet.

4) auto,exec,rw - options for mounting. auto - mount at startup, exec - allow executing files, rw - writable. Write options without spaces (auto,exec,rw)!

5) 0 0 - do not make dump and do not check partition for errors.

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