tc4400 WPA2 AES wireless connection fails

[Account Services]

A customer with a new HP tc4400 tablet running Windows XP Tablet cannot connect to a secured wireless access point. All available Windows updates have been installed. The most recent Intel 3945ABD driver has been installed, dated 10/17/2006, version 10.5.1.72. HP Wireless Assistant shows wireless access ON. The wireless connection's network and wireless properties have been configured. Until this problem is solved, the Windows firewall has been turned OFF, and all third-party security software has been uninstalled. The symptom is that automatic connection does not occur, and manual connection produces a temporary progress bar display that disappears without completing a connection.

The wireless access point is a ZyXEL P-330W operating in bridge mode to distribute a fixed IP network, using WPA2 authorization with AES encryption and a previously shared passphrase. The tc4400 has no problem with wired access to this network, using the same IP configuration being tried for its wireless connection except for a different choice in the final octet, to avoid conflict. A Dell Latitude D520 notebook has no problem with wireless access using this configuration. The tc4400 has no problem with wireless access to unsecured access points. The tc4400 problem with secured wireless access appears to be either configuration or driver capabilities, but there is no obvious indication of what might be wrong. A call to HP Tech Support yielded only some suggestions to check for updates and try disabling security software. Those things have been done, but they did not help. We find, when revisiting properties of the wireless connection after it has been configured and then tested by trying a manually initiated connection, that the WPA-PSK authentication selection we made has been changed back to Open.

[Al Licause]

If this system is running a Microsoft operating system, you might want to post to a more appropriate forum. This forum discusses linux network issues.

[Account Services]

Thanks. We solved the problem. The trick is a Microsoft "hotfix" for Windows XP. Posted over here as well because Linux users are often more knowledgeable about network configuration issues than Windows users.