I'm having similar issues--can't connect to iTunes store. I did a clean uninstall/reinstall and that fix it. I'm running iTunes as an administrator and Windows Firewall is setup to allow iTunes through. Diagnostics pass, yet iTunes store does not load. One other interesting bit is that my other laptop on the same wireless network connects fine.
Microsoft Windows 7 x64 Home Premium Edition Service Pack 1 (Build 7601)
Hewlett-Packard HP ENVY 17 Notebook PC
iTunes 10.5.0.142
QuickTime not available
FairPlay 1.13.35
Apple Application Support 2.1.5
iPod Updater Library 10.0d2
CD Driver 2.2.0.1
CD Driver DLL 2.1.1.1
Apple Mobile Device 4.0.0.96
Apple Mobile Device Driver 1.57.0.0
Bonjour 3.0.0.10 (333.10)
Gracenote SDK 1.9.3.494
Gracenote MusicID 1.9.3.106
Gracenote Submit 1.9.3.136
Gracenote DSP 1.9.3.44
iTunes Serial Number 00E5ABBC034122D0
Current user is an administrator.
The current local date and time is 2011-10-14 21:10:30.
iTunes is not running in safe mode.
WebKit accelerated compositing is enabled.
HDCP is supported.
Core Media is supported.
Video Display Information
ATI Technologies Inc., ATI Mobility Radeon HD 5850
**** External Plug-ins Information ****
No external plug-ins installed.
iPodService 10.5.0.142 (x64) is currently running.
iTunesHelper 10.5.0.142 is currently running.
Apple Mobile Device service 3.3.0.0 is currently running.
**** Network Connectivity Tests ****
Network Adapter Information
Adapter Name: {2A243AA1-744E-436E-9037-7E3DA262C97D}
Description: TAP-Win32 Adapter V9
IP Address: 0.0.0.0
Subnet Mask: 0.0.0.0
Default Gateway: 0.0.0.0
DHCP Enabled: Yes
DHCP Server:
Lease Obtained: Thu Jan 01 01:00:00 1970
Lease Expires: Thu Jan 01 01:00:00 1970
DNS Servers:
Adapter Name: {7F4974FE-7845-4DBC-BB79-7D508FF2595A}
Description: Intel(R) Centrino(R) Advanced-N 6200 AGN
IP Address: 192.168.0.11
Subnet Mask: 255.255.255.0
Default Gateway: 192.168.0.1
DHCP Enabled: Yes
DHCP Server: 192.168.0.1
Lease Obtained: Fri Oct 14 21:08:03 2011
Lease Expires: Fri Oct 14 22:08:03 2011
DNS Servers: 89.2.0.1
89.2.0.2
Adapter Name: {F8270B8D-5526-4675-BBDB-2613A1A781D9}
Description: Bluetooth Device (Personal Area Network)
IP Address: 0.0.0.0
Subnet Mask: 0.0.0.0
Default Gateway: 0.0.0.0
DHCP Enabled: Yes
DHCP Server:
Lease Obtained: Thu Jan 01 01:00:00 1970
Lease Expires: Thu Jan 01 01:00:00 1970
DNS Servers:
Active Connection: LAN Connection
Connected: Yes
Online: Yes
Using Modem: No
Using LAN: Yes
Using Proxy: No
SSL 3.0 Support: Enabled
TLS 1.0 Support: Enabled
Firewall Information
Windows Firewall is on.
iTunes is enabled in Windows Firewall.
Connection attempt to Apple web site was successful.
Connection attempt to browsing iTunes Store was successful.
Connection attempt to purchasing from iTunes Store was successful.
Connection attempt to iPhone activation server was successful.
Connection attempt to firmware update server was successful.
Connection attempt to Gracenote server was successful.
Last successful iTunes Store access was 2011-10-14 21:02:00.