I have seen various different questions for this problem floating around but either the circumstances arent the same or the solution doesnt work so thought i would post it to see if anybody has any suggestions.

Various domain PCs and laptops appear to randomly give the connection name of "lewis.local 2(Unauthenticated)" - lewis.local being our domain - and provides an exclamation mark where the network type logo is normally shown.

This also appears to happen every time connecting via vpn.

Our setup is:

* 2 servers both running windows server 2003 R2 (x32)
* main server has AD, DNS and DHCP installed
* IPv4 on approx 30 client machines (some wired, some wireless)

If anybody has any thoughts on solutions i would appreciate it. I have tried removing all but AD server roles, resetting all of the systems and nothing. 

It doesnt prevent anything from working just like a domain connection most of the time however it is getting fustrating!

Also dont know if it could have anything to do with it but the DHCP server seems to have quite a long lead time on issuing the IP address to the client.