Backing up the GDFS:
1. "Phone Type" - Choose your phone model here before you start.
If you have a DB2020 phone you can choose any other DB2020 phone from the dropdown list.
So don't worry if you've got a K770 and can't find it in the list
2. "Read GDFS"
SE Tool lite will create a backup of your GDFS.
It will be stored in the SE Tool main folder.
"gdfs_[your IMEI].bin"
Restoring the GDFS:
3. "..."
Select your GDFS backup which you created earlier.
NOTE: Your phone won't work if you flash any GDFS which is not your own backup!!
4. "Write GDFS"
Are you sure that you've selected the correct GDFS file?
If you are: go for it