I just experienced a variation of this issue - my data was not wiped but my partitions were resized and rearranged or merged, I can't say what because I can't make sense of it.
In the installer, I was presented with the 'alongside' or 'replace' options, and after choosing 'alongside' there was no warning, no preview, or a way back. At this point I assumed that the installer would show me a preview and hard-ask me to confirm at a later time, and at a minimum that whatever it would do would be non-destructive, and there was tons of unformatted space for it to use. This is a LTS after all. My starting partitions were something along the lines of: sda1 - 300mb - EFI sda2 - 32gb - Fedora / (ext4) sda3 - 128gb - /home(ext4) sda4 - 8gb - swap unpartitioned - ~80gb I now have (taken from the Fedora install): # lsblk NAME MAJ:MIN RM SIZE RO TYPE MOUNTPOINT sda 8:0 0 238.5G 0 disk ├─sda1 8:1 0 300M 0 part /boot/efi ├─sda2 8:2 0 125G 0 part /home ├─sda3 8:3 0 31.3G 0 part / ├─sda4 8:4 0 7.8G 0 part [SWAP] └─sda5 8:5 0 74.1G 0 part # fdisk -l Disk /dev/sda: 238.5 GiB, 256060514304 bytes, 500118192 sectors Units: sectors of 1 * 512 = 512 bytes Sector size (logical/physical): 512 bytes / 512 bytes I/O size (minimum/optimal): 512 bytes / 512 bytes Disklabel type: gpt Disk identifier: 196DAE4C-D3BD-46CA-B561-BA945C76198E Device Start End Size Type /dev/sda1 2048 616447 300M EFI System /dev/sda2 616448 262760447 125G Microsoft basic data /dev/sda3 262760448 328296447 31.3G Microsoft basic data /dev/sda4 328296448 344680447 7.8G Linux swap /dev/sda5 344680448 500117503 74.1G Linux filesystem -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1265192 Title: Install/reinstall wipes out all/other partitions To manage notifications about this bug go to: https://bugs.launchpad.net/elementaryos/+bug/1265192/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs