new itunes freezing

please help.ever since the new itunes update, my laptop freezes when itunes opens.

it will not sync. will not open, will not close. i have to cntrl alt delete and restart just to

get my desktop back.

i have uninstalled and re-installed ....and cut off my norton antivirus,......still getting

a "this program will harm your computer" message.

thank you in advance for your help.