Get Request not being sent in IE7

[juniper911]

Hello All

Not sure if this is the appropriate forum. I have a number of client workstations (Vista + IE7) trying to get to an intranet site (IIS 6) that requires Integrated Authentication. These workstation fail, after having checked all the IE settings that I know of I cannot see anything to the contrary.

I then did a netmon and found that that initial get request does not contain a HTTP Cookie. This is the only thing that appears different comparing the trace to a working workstation. They both negotiate to NTLM auth, does anyone know what setting would stop the client sending a cookie?

Belated happy new year

 

[tlcscousin]

http://www.1stbyte.com/2008/03/15/i...le-integrated-windows-authentication-checked/

 

[juniper911]

cheers tkscousin for the link, I already came across this and tried what was suggested but it did not work.

When looking at the netmon trace I can see the NTLM handshake and on the first round trip the client does not give a cookie, where as those working clients do. Now I come across another laptop in the same site where it does not give a cookie, the web server responds with a 401.2 and then the client comes back with another Get Request and this time there is a cookie. I think its a reg setting that is not applied to those boxes but not sure what key?!!

 

[juniper911]

MTU Setting!!!

The default of 1500 was too big, dropped it down and now it works!! yippee

 

[Sympology]

Strange....

Are these on a Internal LAN / WAN? It could indicate you have a networking issue, with fragmented packets not being routed correctly



Robert Wilensky:
We've all heard that a million monkeys banging on a million typewriters will eventually reproduce the entire works of Shakespeare. Now, thanks to the Internet, we know this is not true.

 

[juniper911]

Default MTU is 1500 minus the overhead of 28. A network device had an MTU set lower which results in packets between the client and IIS server being dropped so it could not authenticate. Changed the MTU on the IIS server to be the same size of the network device and now the client can authenticate. MTU needs to be only set on one side.