Refer to this article to delete SC files:
iTunes for Windows: Doesn't open after upgrading in Windows Vista or Windows 7
Then repair your Quicktime.
Control Panel/Programs n Features/highlight Quicktime and click Repair button.
I am also having a problem with Itunes 64bit in Windows 7. It was working fine until a few days ago and now it will not open. When it does, it becomes unresponsive. I have tried the above, no luck. I tried repairing it, nothing. I have uninstalled an reinstalled-again it either does not open or it immediately becomes unresponsive. I have checked for malware with Malwarebyes, nothing was found. i think there is probably a problem with one of my settings or perhaps a file is missing/corrupted-but I don't know how to check. It will not open in safemode.
any suggestions would be appreciated.