Hi I have the following scenario:My laptop is connected in the customer network, that has a domain, but my computer does not join this domain, I only use internet and map some networks drives. So, when I tried to map the network drive everything went ok, but when I tried to connect to the company's proxy it was not possible to be authenticated in it. I disabled the windows integrated authentication in IE8 and input the correct credentials for the proxy, but it did not work, a message was shown telling that the proxy authentication failed. I've compared all the Windows 7 settings with my Windows Vista, everything seems to be ok. Does anyone have a hint about this issue?Thanks Very muchDaniel

Does the issue occurs when using a third-party browser?Please try to clear the IE cache and history and try again. If you have a domain account, please try to type the user name as <domian name>\<username>Thank you.

Hi, thanks for response, I've done it but the problem is still happening. Can it be incompatibility with the network? thanks

Hi dburla,Do you mean that the issue occurs even we use a third-party browser?In some cases the "proxy authentication failed" issue might be caused by the incompatibility between the proxy server and the clients. In that situation, we can try to update the proxy server to the latest version to see if that helps.Based on current information we have. We cannot say what the root cause is. It depends on the configuration of the proxy server. Would you please let me know what the proxy application is? (ISA server or third-party proxy server)? I understand that you maynot have adminitrative permission on the proxy server. In this case, you may need to contact the administrator for furhter troubleshooting.Thank you.

hi denisxu,Even if use 3rd party browsers the problem occurs. I think the problem is related to the proxy. I'm trying to get information about the proxy used in the company's environment.Thanks again

Hi denisxu,I managed to how to bypass this problem, I did not find out what proxy is used here, but I used thefollowing steps to solve the problem:"The problem is the autentificacin NTLM of Windows7. It is necessary to create the following key in the registry to solve it (I'm using Squid Version 3.0.STABLE8 in Debian Lenny): 1. In HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Lsa If it doesnt exist, create a DWORD value named LmCompatibilityLevel and set the value to 1 to use LM NTLM and NTLMv2 if is negociated, this is Also it works establishing the value to 0, and 3 though for more safety the value using 3 though with old operating systems it will not work on having used obligatorily NTLMv2. 2. Reboot To follow the link for more information: http://technet.microsoft.com/es-es/magazine/2006.08.securitywatch(en-us).aspx"Source: http://www.nabble.com/Windows-7-beta-and-NTLM-td21377271.htmlThis worked well, now I'm able to connect in internet through proxy server.Thanks

Hi Denisxu I am using squid proxy stable 2.6 and on client side am using windows server 2008 With your solution in the above thread my IE authentication problem has been solved But when I try to update windows through windows update Its again asking me for proxy authentication and its not accepting