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UTHENTICATION 

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Additional Tips 

If the attempt to obtain a DHCP address fails due to a timing issue (the authentication process was not successful 

before the DHCP request timed out) the client may not have a proper DHCP address.  Once authentication is 

successful and a network connection is granted by the Foundry device, Windows 2000 Professional (SP3 with all 

802.1X patches) and Windows XP (SP1) clients should renegotiate a DHCP address with the DHCP server after a 

short period of time. 

If this is not the case, you can manually release and renew the DHCP address with the following command line 

C:\> ipconfig /release 

a DHCP address.  An example of the batch file commands are: 

ipconfig /release 

pause 

If you need to manually control the Local Area Connection authentication prompt, temporarily disconnect the 

network cable from the client for 10 seconds and then reattach it.  This will trigger a new EAP-MD5 

authentication process and allow the user to enter the authentication credentials again.