first upload the image via usb official r6844...
then make a scan for channels .....
read your db.dat over pc editor beta7 and save ...
upload the image sifteam 0.0.4_r6844
upload the db.dat and reboot ....
you should not get the error 79...
let me ask you then how long you have the box if you know so much....???
and why you need to rename the db.dat file...???