Help HELP!! Phone stuck in boot loop

[Thomo18]

Help me please,

I encrypted my phone earlier today using the stock method on the GT-I9305, about an hour ago my phone froze on a black screen with the blue LED indicator.

I pulled the battery and rebooted and after putting in my encryption password the phone gets stuck in the Samsung boot loop.

When I open system recovery I get the following:

E:failed to mount /data (invalid argument)
can't mount '/data' (invalid argument)

Please can you help me rectify this

 

[Thomo18]

I have managed to solve it with a factory reset, unfortunately hadn't backed up my phone so if anyone has a good guide to that it would be appreciated

 

[hackler007]

Not sure what your really asking since you manage to get your phone out of the boot loop. As far as the back up few methods can be done. Are you using a custom recovery? If so you can do what is called a nandroid backup on ClockworkMod or TWRP. Now if your phone is stock you can use an app called Elite Backup ★ no root Here: https://play.google.com/store/apps/details?id=app.backup.titan.ads&hl=en.
They have many others if you choose to but this is just a guide for you question. As far as putting in your encryption for your data be careful and ask around to get it done correctly without losing any data or soft bricking your phone. Good Luck.