FileVault encryption stuck High Sierra Beta 5

You're not the only one. I posted about this on here a few days ago, and when searching for "File Vault" on here see a lot of other threads with people having the same issue. So far no resolution.

I'm not sure my experience is directly the same but when going from Beta 5 to Beta 6 it failed, saying it could not install Beta 6 because the volume (my hard drive) was being decrypted. The decryption was at 99% but would not finish. I tried all manners to abort the decryption without success. Almost all the advice I read said to let it finish. So I waited and four days later it finished. Then everything worked OK.

In my experience with both High Sierra Betas 5 & 6 and a Retina MacBook Pro 13" TB model, I'd stay away from File Vault for now.

1. I performed a clean installation from a USB flash drive and formatted the System volume as APFS (Encrypted). I was prompted for a Disk Password, and upon every reboot was asked to provide this password to first access the disk. I then encrypted the System volume following initial installation with File Vault, which took a few hours but completed successfully. From that point on, I was first asked to enter my Disk password, followed by a second request to enter my User/Admin password at each startup. File Vault did not seamlessly allow for the entry of one password, which I suppose is by design.

2. I next disabled the Guest User Account and restarted. To my surprise, not one but two Guest User account logins were presented in the startup screen! I could never get rid of them.

3. Finally, I changed the default location of my Home folder to a second partition, where I store all my music, documents and video files. I was prompted to restart, but when asked to enter the Disk password after booting, my password was no longer accepted! I tried to access (mount) the System volume from the recovery partition with the same password, but was not successful. So I was forced to reformat the volume as APFS and restore my system from a Time Machine Backup, which thank goodness again allowed me to get back to work!

Same thing happened to me. I was prompted and stupidly said hey why not it must be featured in this beta or something. BIG MISTAKE. I also had "one minute remianing" for two days with enabled and 0% showing in terminal. I was told by many to leave and wait it out, could take a few weeks. I lost paitience with the inability to do any instll anything or updates until it was done (doing nothing).

I reformatted and reinstalled from a backup. I also see a ton of references to File Vault issues in the current release notes. I'll stay clear of FileVault probabbly forever, but definitely until the final release.

I was having the same issue with Public Beta 5. Tried all the stuff that's been suggested.

I think this is what finally did it...patience.

1. Boot in safe mode.

2. Turn off screen saver

3. Set screen to never sleep.

4. Turn brightness all the way down (so as not to damage your screen and let it run overnight)

Same thing happened to me, I just tried StroobyDoo solution and it did relaunch the process that was stuck at 91% for ages, it is now going on (at 93% right now). You can restart your laptop in "classic" mode once the process restarted it you need to (at least it work on mine) as Safe-mode can be a bit restricted.

I am having this same problem with FileVault in High Sierra Beta. I am going to try leaving it on overnight and see what happens.

I have had my mac working on decrypting the hard drive following your instructions for 2 days now. It has not progressed. Any other thoughts?

In macOS Big Sur I found a rather simply trick: Simply cause I/O to an APFS volume which is stuck in partial FileVault encryption. Simply copy a file to that volume and delete it again. That re-triggers the encryption process, where no other method re-triggered it!

With diskutil ap list <YourDiskID>the status of Encryption Progress changed from xx.x% (Paused) (Unlocked) to then xx.x% (Unlocked)

Worked for an external USB 3.1 attached SSD with a bootable volume stuck in initial FileVault encryption while being booted into my internal SSD. A scenario which as of Apple Silicon Macs and macOS 12+ will anyhow not be supported anymore.* But nevertheless I wanted to share my positive workaround. It may also work being "stuck in initial FileVault" encryption in whatever scenario, maybe also when just plainly encrypting the internal disk (SSD) or non-bootable external disks too.

* Read more at: bombich.com/blog/2021/05/19/beyond-bootable-backups-adapting-recovery-strategies-evolving-platform