Whenever I click Update or Restore, my phone goes into Recovery Mode. Then I have to close iTunes and re-open it in order to restore. I can't update at all. My phone was 1.0.2OTB, so I'm pretty sure it has a 3.9 bootloader. My dad bought both of our phones on the same day, and gave me mine for Christmas. He has the exact same problem I do. Is there any way to fix this without opening my phone?

I've asked a ton of people and tried almost everything. I can't get this to work. I can't get to 1.1.2 because of this.