I'm going to try and put this is as much of a chronological order as I can. Hardware: HP Proliant Microserver Gen8 G2020T 4 x 4Tb WD Red drives, 8Tb RAID 5 and 2Tb RAID 10 128Gb Samsung SSD (root, swap, etc) 1Gb SD card (boot) (This is the boot drive due to the peculiarities of the HP hardware - the SSD cannot be set as the boot drive) Until recently I was running Ubuntu 14.04 on a headless server as a sonarr/Plex box. After a couple of power outages, then internal fan for the server failed, and I replaced this with a standard case fan. Later on, the system seemed to be having some difficulties, only successfully booting intermittently. (I wasn't generally seeking to reboot it, but on occasion had to do so). When troubleshooting this, I vaguely recall something about being unable to write to the root drive, but I cannot recall the specific cause/message. This weekend I decided to have a go at getting it working again - which involved taking my monitor, keyboard and mouse from one end of the house to the other, as the server has no WiFi. As a result, my ability to comprehensively troubleshoot was somewhat limited. I managed to successfully get the system to boot by selecting an older kernel (3.13 version, with 148 being the most recent functional, and 170 being the most recent actual) - however I didn't trust that this was stable, and I also realised that 14.04 had reached end of life stage. Given that the system was running fine, I decided to update to 16.04 as a stepping stone to 18.04. Moving to 16.04 seemed to go fine, with everything downloading and installing without issue. A new kernel was also applied, 4.4, with the 3.13.170 kernel being retained. On boot however, the system will get to GRUB and give me 6 options (3 for each kernel) of normal, upstart and recovery. In each instance the system seems to either hang at "loading initial ramdisk", or loads into "BusyBox", and that's where I am stuck. I have tried booting onto a live USB of 16.04 and running boot-repair, but that said everything was OK. I have also tried running fsck on the Samsung SSD (root drive), but that seems to go into an infinite run of error discovery. Other than simply attempting to install a totally new version of Ubuntu onto the drive, what are my options here? Is there anything I can do to attempt to diagnose/check/repair the SDD on my windows machine? If I do have to go down the route of a new OS install, will I still be able to access the data on my storage drives, or am I facing a total loss here?