I have recently encrypted my S3 to allow me to get work emails, but I have now decided against this as it has caused the phone to run like a dog. When I attempt to decrypt the device it says I need to set a password of 6 characters with at least one number, however when I go to the lock screen settings menu password is not an option. I have deleted the email account and I am not sure what to try next. Can someone point me in the right direction please?
Here is a last ditch solution if you get nothing better:
If you know how to use John The Ripper then all you have to do is pull all of the files off of your hard drive, and use JTR to crack the password (depending on the length of the key, this could take days or even weeks). Then you can make an image file of your hard drive and flash your device using a flashing tool.
Besides that, I'm sure there is no way to disable the encryption without the key. Really your only option at that point is to get any files off of it that it will allow you to, and then do a factory reset.
As far as I know, reverting the android encryption is impossible, you will have to backup your information and perform a factory reset.
It is possible to decrypt an android. I am doing it right now. I had to turn off the maas360 device admin using the app itself: you can't do it from the device admin screen. Once I did that, I had the decrypt option. The decrypt worked fine for the phone, and I am doing the sd card now. I still only have the password option for the lock screen, but hoping this sd card decrypt gives opens the other options. I have a Verizon G S4 running 4.4.1.