I changed my mobile operator and needed to use a new SIM card, so I turned off my Samsung Galaxy J5, replaced the old card with the new one and restarted the phone. After rebooting I noticed that all my messages and photos were gone. Unfortunately, when I put the old card again, the data was still lost.
I have a couple of questions. Firstly, why was the data lost? Is that some kind of security mechanism to reset the phone when a new SIM card is used? Can it be configured in the settings? I didn't recall having similar problems before on other android smartphones.
Secondly, was the data really erased or is it possible that the photos are still somewhere on the phone, but due to the cards swap I can't see them? I checked all the folders on my phone after plugging it to my laptop, and the photos seem to be really gone, but I want to make sure before trying to use any recovery software.
And the last question - if the data was really lost, is it possible to recover it with unrooted phone? It seems that I can't force my phone to connect with USB mass storage mode, so using apps like Recuva is not possible. All the other Android specific apps that I found required the phone to be rooted. Are there any alternatives?