C510 Master reset
If you select Reset settings, the changes that you have made to settings will be deleted.
If you select Reset all, your settings and content, such as contacts, messages, pictures, sounds and downloaded
games, will be deleted. You may also lose content that was in the phone at purchase.
To reset the phone
1 From standby select Menu > Settings > the General tab > Master reset.
2 Select an option.
3 Follow the instructions that appear.
When your phone is frozen pull out battery and reinsert it. Turn on your C510.
Restart your C510 phone every day to free memory or do a Master reset.
Use PC Companion
Direct link to PC Companion for C510:
or use old PC Suite
If nothing works: As last resort do a Sony Ericsson phone repaire with PC Suite. USE THIS METHOD FOR hard reset AFTER INSTALLATION----> TOOLS > PHONE REPAIR
Before you buy a new cell phone or new tablet, please try the following procedure to repair your device. First charge your battery, backup your important data if possible and in most cases take out SIM and SD card before factory reset. It is impossible to recover your data after doing a hard reset, so online backup is always important. For all of your data, a backup should be done on an external device, hard drive, raid system or media. With or without insurance, if your cell phone lost, damaged or stolen at least your invaluable data is backed up in a safe place. If you are about to sell your phone and you want to wipe your personal data, or if your phone affected with virus you have to do a hard reset. In some cases, you can delete the forgotten password or lock pattern from your device as well. All information is for devices with stock based ROMs. If you are using rooted device, always back up your EFS folder first, containing your IMEI info, etc.!