If it's locked on the main screen and won't load, follow the below process.
If you want to unlock maps, you need to buy a key or update here:http://eu.mio.com/shop/index.php?language=en-eu&utm_source=callcentre&utm_medium=email&utm_campaign=MTUKLaMa&no_cache=true¤cy=EUR
To reload the software:
1. Connect your device to the computer
2. Make a backup of your addresses and favorites if you wish
3. In File Explorer, right click on the device (removable drive) >> Format
4. Start the Desktop
5. Go to My Mio >> Reinstall the software
6. Go to My Mio >> Recover Keys
7. You can now reinstall the maps from the Maps tab. If you downloaded a map update, make sure to use the downloaded file.
8. Go to My Mio / Voice Transfer and re-install the voice files