Itunes has stopped working error!

When I double click iTunes to start up windows error pops up and says iTunes has stopped working? Why is it doing this? How can I fix this? Please let me know.

Steps I have done:

I have uninstalled and reinstalled it 2 times.

I uninstalled QuickTime

I restarted my computer 4 times.

I have even put a cd to watch a video and the windows pops up with the same error with iTunes has stopped working.