My SGS was confiscated at school about 2 months ago by the school adminstration because bringing phones to schools wasn't allowed. I had removed the battery and SIM when it was confiscated. By then it was running on Onecosmic's ICS 4.0.3 RC3.1 ROM. It was working perfectly with a custom boot animation. Today I got my SGS back and it wont fully boot. When I turn it on I can see the Galaxy S GT-I9000 text plus the 'WITH OUR POWERS COMBINED WE ARE...PLATYPUS KERNEL' logo but it stays black after this. The menu and back button light up on touch but there is no response or activity on the screen.
I have tried almost everything from wiping every data to re-rooting it, blah...blah. I installed 2.3.5 and it works, 2.3.6 ValuePack works too and even CM7 works fine. But it won't accept ICS. Any idea why, please help?
EDIT: I can enter both recovery mode and download mode.