Last year I installed a preview of Windows 10 for Phone (version 10.0.10149) on my Lumia, and it broke both WiFi and the cellular network. Thus I was not able to use the phone or update it with newer previews of Windows 10. Using recovering tools will erase all my data, but I believe my backup was incomplete.
I backed up to my Microsoft account before I installed the preview. However, judging from the size of the backup, I believe data of a particular app wasn't backed up. Is it possible that an app can choose to opt out from the backup, though?
Now that I can view all the "system" files on my phone, by exploiting a bug of the File Explorer, I want to find the place where this app stores data, and copy these data to my PC. The only place I know where an app stores data is the Isolated Storage, so where can I find it in the file system? I can confirm that
C:\Data\Users\DefApps\APPDATA are not the place.
Other methods that allow access to data of an app installed from App Store are also very appreciated.