NOTE: You can check this thread for instructions on how to back up data on the phone.

Restore Contacts from SD Storage:

  1. Launch “contacts
  2. Tap “menu” > “Settings
  3. Go to “Contacts to display” and select “All contacts
  4. Tap “Import/Export contacts” > “Import from SD card
  5. Press “OK” to confirm

Restore Media Files from SD Storage:

  1. Launch “My Files
  2. Go to “SD Card” and tap “Menu
  3. Tap “Edit” and tick the boxes associated with the media files you want to restore
  4. Tap “Menu” > “Move” > “Internal storage
  5. Tap “move here” > “Create folder
  6. Select the desired folder and tap “Move here

Restore Media Files from a Windows PC:

  1. Connect the Android device to the PC via USB
  2. Enable “Media device” / “File Transfer” on the phone, when prompted or from the Notification area
  3. Launch the File Explorer on the computer
  4. Copy and transfer the files to the phone storage, preferably in the folders of origin
  5. Once done, eject the phone storage and safely disconnect the device from the USB port

See More: Samsung Galaxy Sol 3: Restore Contacts and Media Files