This is for those who get error(s) installing Stock Rom after Custom Rom.
I personally have semi-bricked my phone (SGS) a considerable amount of times and each time i got this message :-
E: Can't mount /dev/block/stl10 (invalid Argument) Error.
Then,I got very frustrated and found a fix.
So here is how I fixed it :-
The error is :-
Can't mount dbdata/..........
Install " dbdata.rfs.tar " via Odin in the Download Mode
( Volume Down + Home Key + On/Off Key )
( Odin > PDA > dbdata.rfs.tar )
Note that " COM " will turn yellow after you connect your Samsung Galaxy S GT I9000 to your PC !
This will fix the error(s) !
Hit Thanks if you find this useful !