[Nexus 6  General] bdorr1105:
I seen a lot of Discussion On this topic, and found a really simple way to disable Forced Encryption and it also removes the warning at boot. This in NO WAY is my work at all. I am sharing this [FIX] FED-Patcher v7 (ForceEncrypt Disable Patcher) which was posted by [MENTION=362563]gladiac[/MENTION]. Absolutely make sure you head over to his forum and hit the Thanks button. This works great

Screenshots Below

I have the option to encrypt the phone as you can see circled. I went into system with Root Explorer and was prompted for R/W access and obviously I granted it. Everything is working great!

Preparation

Before proceeding, enable Developer options and MAKE SURE USB DEBUGGING IS ENABLED!!!

1. Download fed_patcher_v7-signed.zip and check here to verify the latest version

2. Download [BETA][2015.10.10] SuperSU v2.52 by [MENTION=631273]Chainfire[/MENTION]

3. Download Whatever ROM you are going to use. I am currently running [ROM]【6.0】LightROM - Marshmallow【MRA58K】- 10/08/15

Instructions

1. Backup your SD Card, during this process, everything will be erased during the process

2. Reboot into TWRP, this is important that you actually have TWRP

3. Perform a Full Wipe by doing the following:

Press Wipe

[*] Press Advanced

[*] Click every check Box

[*] Wipe 3x for good measure

[*] Press Home button

[*] Press Wipe

[*] Press Format Data

[*] Type yes in the box to perform the format

[*] Perform this 3x for a good full wipe

4. Reboot TWRP (Do Not Install Super Su Yet)

5. Once Back In Recovery, On the computer, open My computer

6. Navigate to and open the Nexus 6 Drive

7. Drag the Zip files below to your Phone -

1) fed_patcher_v7-signed.zip

2) BETA-SuperSU-v2.50.zip

3) ROM Zip

If You are Having Trouble, take a look at the screen shots below

You Want to make sure you mount data if it is not, and make sure MTP is not disabled! Thanks [MENTION=6680241]jamiejames[/MENTION] and [MENTION=5238697]aliasferno[/MENTION]

8. Flash your ROM 1st (DO NOT BOOT AFTER FLASHING)

9. Wipe Dalvick Cache/Cache 3x

10. Flash fed_patcher_v7-signed.zip

11. Wipe Dalvick Cache/Cache 3x

12. Flash BETA-SuperSU-v2.52.zip

13. Reboot and Enjoy with no more red error sign during boot and no encryptionhttps://source.android.com/devices/tech/security/verifiedboot/verified-boot.html#user_experience

Supported Devices

Motorola Nexus 6 (shamu)

Version History

v1 - Initial version with HTC Nexus 9 WiFi (flounder) support

[*]v2 - Added Motorola Nexus 6 (shamu) support

[*]v3 - Added support for HTC Nexus 9 LTE (flounder_lte)

[*]v4 - Added support for signed boot-images

[*]v5 - Changed error handling to compensate for missing fstab files. Some roms seem not to ship with the complete set of boot-files from AOSP.

[*]v6 - FED-Patcher will enforce the same structure for the patched boot.img that the original boot.img had. Additionally, the kernel commandline will also be taken over. This should fix pretty much every case where devices would not boot after patching.

[*]v7 - FED-Patcher will now disable dm-verity in fstab to get rid of the red error sign on marshmallow roms.

What Do I need To Make This Work?

A supported device (Your nexus 6)

[*]An unlocked bootloader

[*]An already installed ROM with forceencrypt flag. (like cyanogenmod CM12.1)

[*]A recovery that includes busybox (TWRP, CWM)

How Do I Use it?

Follow Instructions above - This is the basic need to know information

[*]Make a thorough, conservative backup of your data if there is any on your device

[*]Go into your recovery (TWRP, CWM)

[*]Flash fed_patcher-signed.zip

[*]If your device is already encrypted (You booted your ROM at least once) you need to do a full wipe to get rid of the encryption. This full wipe will clear all your data on your data-partition (where your apps as well as their settings are stored) as well as on your internal storage so please, do a backup before. If you don't do a backup and want to restore your data... well... Call obama.

IMPORTANT: If you update your ROM you have to run FED-Patcher again because ROM-updates also update the boot-partition which effectively removes my patch. So, if you are on CM12.1 for example and you used my patch and do an update to a newer nightly you have to run FED-Patcher again. If you don't do so Android will encrypt your device at the first boot.

Is It Dangerous?

Well, I implemented tons of checks that prevent pretty much anything bad from happening. But, of course, we're dealing with the boot-partition here. Even though I tested FED-Patcher quite a lot there is still room for crap hitting the fan.

All Thanks To:

[MENTION=362563]gladiac[/MENTION] - For Putting the OP together for the Nexus 9 and sharing this

[*]@rovo89 - for his xposed framework - I used some of his ideas by reading the source of his xposed installer flashable ZIP for FED-Patcher.

[*]@pbatard - for making (un)mkbootimg (dunno if he is on xda)