Just started today. Was able to let it automatic repair and boot up. Was on for like 10 hours, shut down and tried to boot up some hours later. Now its completely stuck on automatic repair. Have unplugged all additional hdd's and then all unnesscarry USB's. Still doing this. Also removed my ethernet card. Still the same.
I cannot lose my data. I have several SSD's and HDD's with important files across several of them.
Is your data encrypted? If not you can simply remove the c drive from your computer plug it into an external kit and view the contents from another computer.
Also, if you do connect it externally and you discover that the disc has issues and it's not just a memory problem or something, do not under any circumstances do a disc fix. I lost to drive that way, 2 TB of information just poof. So if you are able to access the drive but there is actually some issue with the drive just remove the data little by little as you can no matter how long it takes.
Edit: I should have added, you can also use a pre-installed environment OS or an operating system on a thumb drive to access your data. Though I would say for diagnostic purposes removal of the drive to an external kit tends to be better at separating issues with the drive from issues with your actual computer.