Whenever a hard reset is performed, it is obvious that all the user data in the device (photos, videos, songs, contacts, email data, maps and other app data) will be erased. This kind of hard reset can be done by going to Settings -> About -> Reset your phone or by a key combination.
What is unknown till today to most of the world is there exists a special way to hard reset a Windows Phone, which has been discovered by winuser.ir.
Type the following code from the dialer of your Windows Phone. Do nothing more and a warning as shown in the above picture will be displayed.
The advantage of performing a reset in this way is that, the maps data can be kept safe even though the other user data will be lost. This can help in saving a lot of time as user does not need to download the map data of his region again, which accounts to over 100 MB minimum.
The above image shows a Lumia 730 after the above code is entered in the dialer. I have tried the same code with a Lumia 1020 too, but did not get the warning message as expected. I cannot judge if this is due to the fact that the device is running in Developers Preview mode or if this code is device restricted. If you encounter a similar issue with your Lumia 1020 or any other Windows Phone, do not forget to mention it in the comments!
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