How to Turn Off FileVault

If you've accidentally (like I did) or intentionally activate FileValult on your boot drive and want to remove it here is what you need to know:

1 - first if you've accidentally turned on FileVault have patience, lots of patience. It can take the better part of a day or more to encrypt the drive. All you can do is wait. For my 200 GB of data on my SSD boot drive it took around 8-9 hours to complete. For a rotational drive much longer as well as longer for more data on the drive.

You can continue using the Mac while the encryption is going on. I just didn't shut down but left it on until it completed even if I wan't using the iMac.

2 - once the encryption is complete go back to the System/Security and Privacy/FileVault preference pane, click on the padlock to unlock the pane and click on the Turn off FileVault button.

I left the decryption go on overnight but don't know how long it actually took.

These instructions are based on this Apple Document; .macOS Sierra- Turn off FileVault encryption.The earlier link in this post will take you to the directions for turning off FileVault in this document.