Reinstalling Ubuntu 12.04

[ubienewbie1]

This is maybe because you didn't boot into Live mode, which is essential for Gparted to Delete whatever partitions your current installations have...

When you boot from your machine, the partitions gets mounted.... and there is no way you can delete them when they are mounted.. so the idea of booting into live mode is suggested so that they dont get mounted and you can delete them without any hesitations... Good Luck with gparted... hope this helps..

I actually tried it both ways with the same results.

[darkod]

I actually tried it both ways with the same results.

In Gparted, if you see a keys symbol next to a partition, that means it's mounted and can't be deleted. Now, contrary to popular belief, booting into live mode itself is not enough in some cases.

If there is an existing swap partition on the hdd (and in your case there was), the live mode will mount it to use it to work faster. If this swap partition is logical (inside the extended partition), and also if the root is logical, that will make all of them blocked for deleting since they are all together in the extended partition.

In Gparted right-click the swap partition, and select Swapoff. That should remove all keys symbols. After that you can manipulate them.

Deleting the partition is not necessary if you are happy with their sizes and you simply want to reinstall. But to re-use existing partitions you have to use the manual partitioning during the installation, not the auto method. In that case, you click on every partition you want to use, then select the Change button below, and in the window that shows select what to use the partition as, and the mount point. Also whether you want to format it or not.

Since some people "get scared" as soon as you say manual partitioning, and prefer only using the auto methods, for that you need to delete the partitions first and leave the space as unallocated for the autoinstaller to use.

How you do it, is up to you. i always prefer manually because it gives you most control.

[ubienewbie1]

In Gparted, if you see a keys symbol next to a partition, that means it's mounted and can't be deleted. Now, contrary to popular belief, booting into live mode itself is not enough in some cases.

Thanks for confirming that I'm not entirely crazy.

In Gparted right-click the swap partition, and select Swapoff. That should remove all keys symbols. After that you can manipulate them.

I had done that, but I still couldn't unmount the main partition. I did get everything working finally last night with a Mint installation (sorry, I was running out of options and patience) on the first try. The partitioning menus are all the same, and I followed the exact same process as all the failed Ubuntu installs except for one small difference: With the Mint install, I specified "new partition table" before applying the partitions. Nothing that ensued seemed any different, so I'm not sure if that actually mattered. But, maybe the lack of a partition table previously was screwing things up, including the inability to unmount the main partition? (If so, you'd think the manual partitioning mode would have a safeguard against proceeding like that.)