Protect files from being deleted and Acronis 2015 problem

Dear Sir,
I used to create Tib image file for my kids drive C: by the use of Acronis 2015 bootable CD, however they deleted it which prevents me from restoring their PC fast and I have to restart over from scratch.

So I decided to try to protect this Tib file, I proceeded as follow:
1) Create another admin user for me
2) Log in to my account
3) Take ownership of original Tib files
4) Deny another users from accessing or deleting these files
5) Hide admin user from log in screen
Then I tested the result by booting with Acronis 2015 CD and tried to restore the image. When I selected the image I got error : True Image backup archive is corrupted .. etc
Then I restarted PC and remove the protection (granted access for their user) and tried again by Acronis just to receive same error.

I repeated the procedures many times, and found when a backup permission is set to access denied; True image says it is corrupted. I if I did not set it as access denied True image would proceed normally.
Is there anything I can do in this regard to protect Tib image and let Acronis accepts it?
Operating system is Windows 7 Ultimate SP1
Best regards
Alaa Mostafa

I am not clear why your booting from CD to do this and we're your backing it up to another PC or kids pc? The normal way of doing this is either run it as a task and back it up to another pc via network or set acronis to back it up to secure zone so to restore you press a key on start to do recovery

Dear samurai
Thank you for replying.
Acronis is not installed in my kids PC. And I am storing image file on a partition of their PC not a network drive. My idea is, in a time of a disaster many options – such as a network drive - would not be available. So if the image is in a local HDD, that would be the easiest and faster way for recovery.
Best regards
Alaa Mostafa

Then install it create a backup job setup secure zone so if it breaks you press a key on boot to recover using a secure zone it backs files to a hidden partition so job done

Dear samurai

Thank you, but don’t you have an option other thaninstalling Acronis of their PC.

What I want is to protect Tib file and in the same timemake it available for Acronis when booting from CD.

Best regards

Alaa Mostafa

With the secure some you can see the file and it's a separate partition

Would you please explain; what do you mean by "secure some"
Best regards
Alaa Mostafa

We secure zone on the phone it changes spelling it a hidden partition that acronnis creates for images

Dear samurai
Thank you for your support
Dear RonalJS
Yes, now I am convinced that storing images on external HDD is the best choice.
Many thanks
Best regards
Alaa Mostafa