Can't connect to the italian iTunes Store from Windows 7

Hi everyone,

It's been more than a month since I bought my new notebook (running Windows 7, details below), and I still can't connect to the iTunes Store.

Here is the message:

"We could not complete your iTunes Store request. The iTunes Store is temporarily unavailable. Please try again later."

I followed every step of this guide, without success.

My connection works, every PC in my house can connect to the iTunes Store with my account, even iCloud logged in on this computer.

Here is my iTunes Diagnosis windows about connectivity test:

(Sorry, it's all written in italian, but basically it says that it's all ok like you can see from the green dots)

I've already contacted Apple Support but they didn't solve my problem, they just told me to follow the guide on this site.

Please, help me! It's driving me crazy!

Details:

OS: Windows 7 Ultimate 64 Bit Service Pack 1

iTunes version: 11.1.3.8

Notebook: Toshiba Satellite L50-A-170 PSKJNE