Itunes doesnt let me put the custom fw on.... always that error 21...
then it stops.
What the hell am I going to do - nothings working now...
Have you tried with standard recovery mode.
Unplug the phone, switch it off, hold down the home button, plug it in and keep it held down until you see the itunes and cable on the screen? Then try and update the custom firmware?
Also saw on the internet that reinstalling iTunes may solve it.