Client connections do not authenticate successfully with a Cisco switch when it takes more than five seconds to generate an NAP SoH message on a Windows Vista-based computer or on a Windows XP Service Pack 3-based computer

When it takes more than five seconds to generate a Network Access Protection (NAP) statement of health (SoH) message on a Windows Vista-based computer or on a Windows XP Service Pack 3-based computer, client connections do not authenticate successfully with a Cisco switch.

This problem occurs if the supplicant time-out value for the Cisco switch is lower than the number of seconds that it takes the client to generate the NAP SoH message.

To resolve this problem, change the supplicant time-out value for the Cisco switch to 15 seconds or longer. By default, the supplicant time-out value on Cisco 802.1X devices is five seconds.

For more information about how to change the supplicant time-out value, contact Cisco. For information about how to contact Cisco, click the appropriate article number in the following list to view the article in the Microsoft Knowledge Base:

Microsoft has confirmed that this is a problem in the Microsoft products that are listed in the "Applies to" section.

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