How to completely reset a phone to how it was sold?

Question

I have a LG D380 that was rooted and some unwanted apps were installed on it.

I tried a factory reset but it didn't help.

Is there any way to restore this phone to a state at which it was sold without downloading any software/firmware from potentially untrusted 3rd party sources?

Lindsay mcdaniel · Accepted Answer

If the phone was rooted you should go to the backup that was created of all the apps. Reinstall the apps that were rooted.
Then do the factory reset.
As far as clearing the cash partition,
This is slightly different from phone to phone. You can find the proper method for your device on the internet.

James Watson · Answer

Try a factory reset + wipe cache partition.

tfoller · Answer

How do I do that on LG D380? 
Factory reset doesn't have any option for wipe cache as well as Backup & Restore.

suba1202 · Answer

- First switch off the phone.
 - Hold power button + volume Down
 - Take the  finger from power button once LG is displayed and keep
   pressing volume down.
 - Then press power button once. scroll 'yes' and press power button to
   confirm factory reset

Lindsay mcdaniel · Answer

> [[cite suba1202]]
>
>  - First switch off the phone.
>  - Hold power button + volume Down
>  - Take the  finger from power button once LG is displayed and keep
>    pressing volume down.
>  - Then press power button once. scroll 'yes' and press power button to
>    confirm factory reset
> 
> 

tfoller already did a Factory reset!
They need to know how to clear the cashed partition!