Support for Windows Vista without any service packs installed ended on April 13, 2010. To continue receiving security updates for Windows, make sure you're running Windows Vista with Service Pack 2 (SP2). For more information, refer to this Microsoft web page: Support is ending for some versions of Windows
On a Microsoft Windows Vista-based computer, you may experience one or more of the following symptoms in a wireless network environment.
IEEE 802.1X authentication that is based on Virtual Local Area Network (VLAN) switching may fail.
For example, you try to use computer authentication and user authentication to switch the client computer to different VLANs. However, the client computer does not obtain the correct IP address during VLAN switching.
In a wireless profile, the information about the Extensible Authentication Protocol (EAP) method that is selected in a user interface may be incorrect.
For example, if different vendors provide more than one EAP method, the EAP method that is displayed in a wireless profile is not the EAP method that is actually selected.
A wireless profile that an independent hardware vendor (IHV) provides may be corrupted after you use the wireless profile user interface to edit the profile. When this problem occurs, you may receive an error message that Windows Explorer has crashed.
Every time that you roam to a different wireless access point, you are prompted to provide a user credential. This problem occurs even if you have saved the user credential.
You registered a Protected Extensible Authentication Protocol (PEAP) method that the IHV provided. When you try to authenticate against an Internet Authentication Service (IAS) server, the server may reject the authentication, and the IAS server may send an error message that the authentication has failed. The Onex.dll file crashes when this problem occurs.
Service pack information
To resolve this problem, obtain the latest service pack for Windows Vista. For more information, click the following article number to view the article in the Microsoft Knowledge Base:
935791 How to obtain the latest Windows Vista service pack
A supported hotfix is available from Microsoft. However, this hotfix is intended to correct only the problem that is described in this article. Apply this hotfix only to systems that are experiencing this specific problem. This hotfix might receive additional testing. Therefore, if you are not severely affected by this problem, we recommend that you wait for the next software update that contains this hotfix.
If the hotfix is available for download, there is a "Hotfix download available" section at the top of this Knowledge Base article. If this section does not appear, contact Microsoft Customer Service and Support to obtain the hotfix.
Note If additional issues occur or if any troubleshooting is required, you might have to create a separate service request. The usual support costs will apply to additional support questions and issues that do not qualify for this specific hotfix. For a complete list of Microsoft Customer Service and Support telephone numbers or to create a separate service request, visit the following Microsoft Web site:
Note The "Hotfix download available" form displays the languages for which the hotfix is available. If you do not see your language, it is because a hotfix is not available for that language.
No prerequisites are required.
You have to restart the computer after you apply this hotfix.
Hotfix replacement information
This hotfix does not replace any other previously released hotfixes.
To use one of the hotfixes in this package, you do not have to make any changes to the registry.
The English version of this hotfix has the file attributes (or later file attributes) that are listed in the following table. The dates and times for these files are listed in Coordinated Universal Time (UTC). When you view the file information, it is converted to local time. To find the difference between UTC and local time, use the Time Zone tab in the Date and Time item in Control Panel.