Freezes while connect iPhone

Question

Hi guys, a weeks ago, weird thing happened to my iTunes.
It works fine with music, movies but when I connect the iPhone, it freezes and not responding.
I tried everything I could.
Here is what I did:
1. I have nothing in Podcasts.
2. I tried to make a new libraries, erasing the old one, but still freezes on connection.
3. I created a new mac account then use iTunes on that account with iPhone connected, it worked fine.
What is the problem? anyone can help me?
And please don't say "I have that problem too."

Answer 1

Back up all data.
Triple-click anywhere in the line below on this page to select it:
~/Library/Application Support/SyncServices
Right-click or control-click the line and select
          Services ▹ Reveal in Finder (or just Reveal)
from the contextual menu.* A folder should open with an item selected. Quit the application if it's running. Move the selected item to the Trash. Relaunch the application and test.
*If you don't see the contextual menu item, copy the selected text to the Clipboard by pressing the key combination  command-C. In the Finder, select
          Go ▹ Go to Folder...
from the menu bar and paste into the box that opens by pressing command-V. You won't see what you pasted because a line break is included. Press return.