Samsung Galaxy S2 Wont Start after upgrade attempt

[manjourney]

I tried to update my device (Samsung S2, from T-mobile) and after follow instructions on you tube video I realized that my device wasn't compatible with that upgrade (Android 4.0). I root my phone before, i do something with Odin, well I mess up my phone... Are there is a possibility to fix that?

Thank you!!

 

[PvilleComp]

If you made a backup in Cockwork before your update - you should be able to restore your backup. If not you might have to flash back to stock and root over again.

[HOWTO] unroot Complete stock guide with FAST working links - xda-developers