HelloWe have a 2003 domain running 12 XP clients, last week I installed a vista computers at the site, everynow and again it loses internet connection, connection to the server is not lost, server shares are still accessable i can ping external domains and tracert to msn.co.uk for example but http traffice is not working, I have replaced the router which is now a draytek vigor, setup is:Vista business fully patched, tried running it both as dhcp and static, 2003 serverr2 dns using forwarders to isp, power saving disabled on nic, tried 2 nics.When vista loses's connection it changes to "local only" I can RDP to the client from the server and Ping and tracert to my hearts content, for no reason the "local only" will change the world icon appears, 30 seconds later internet activity comes back, I have put another Vista computer and one new XP in......XP fine, vista doing same as 1st computer.I'm almost at the stage of taking out Vista and putting in XP to cure the problem, tried disabling firewall, av, etc but no change....Any help gratefully receivedJohnFidget

Hi John, Thank you for posting. Based on my research, I would like to suggest the following: 1. Please try disabling the feature TCP Auto Tuning and see if it works. To do this, just run the following command in an elevated command prompt: netsh interface tcp set global autotuninglevel=disabled For more information about TCP Auto Tuning, please also refer to: Windows Vista- TCP Auto Tuning 2. Please also try this method: Windows Vista won't connect to the network If the issue persists, please also capture a network traffic trace on the Windows Vista computer for our further investigation: 1. Download the Microsoft Network Monitor 3.3 from the following link: http://www.microsoft.com/downloads/details.aspx?FamilyID=983b941d-06cb-4658-b7f6-3088333d062f&displaylang=en 2. Install the network monitor and start to capture. 3. Keep monitoring the Windows Vista computer and wait the Local Only appears. Note: Please dont perform operations on this computer while capturing. 4. After the issue Local Only disappears and the Internet connection gets back, stop captureing and save the network trace files to check the related network activations. You can use Windows Live SkyDrive (http://www.skydrive.live.com/) to upload the file and share its URL with us. Thanks.Nicholas Li - MSFT

Hi John, I just want to see how everything is going. If you have any questions or concerns on the recent information I've provided you, please feel free to let me know. I look forward to hearing from you. Thanks! :-)Nicholas Li - MSFT

Hello Nicholas,Sorry for the late reply, I've been working on the problem with MS help but still no joy, so far we have done the things mentioned in your previous post, change net card, changed switch, I've included two captures, the one named PC-14 was taken this monring, internet was not working, then started, the details of the ips address's are:Local IP ofvista PC 192.168.1.1732003 server with DNS 192.168.1.1Gateway 192.168.1.254 DNS server using forwarders which are 158.152.1.43 & 158.152.1.58Captured files:http://cid-836799eb9e1b63d9.skydrive.live.com/browse.aspx/pc14 Thanks for any helpJohnFidget

Hello John,I just posted the same exact posting since I have 4 Vista computers that connect to the Internet when they want to meaning they can be connected for a day and then the next three days they are down or if they are up and I do a reboot they will be down. Have you found a solution with Microsoft?

HelloStill ongoing, what router are you using ?ThanksjohnFidget

I am using a Netgear VPN Firewall router. This issue started last Friday on all Vista computers (4 total). Before that everything was working fine. All my Windows XP computers are working fine. The internet connections work when they want to work. I don't understand this...and I know we aren't the only people having this isssue. I am in several forums and we have tried everything....

John / TechsI recently opened port 443 on my Netgear VPN Firewall and installed a GoDaddy SSL certificate to resolve the issue with my iPhone receiving company Exchange email. After doing that all the WIndows Vista computers stopped getting connectivity meaning there Internet and company Exchange email stopped working. I have a previous ticket open now to resolve this issue under WIndows Vista but I now think it has something to do with the WIndows 2003 Server, Exchange 2003, or IIS v6.0 because we tried everything. I need to get this issue resolved as soon as possible since management is using the WIndows Vista computers. We only have 4 WIndows Vista computers that aren't working and about 25 WIndows XP computers that are working fine. After all this I removed the SSL certificate and closed port 443 and I am still having the same problem so I think something on the server is causing it.Any Ideas?

Hi, Thank you for your update. I suspect that the issue may result from the Neighbor Caches feature in Windows Vista. To isolate the issue, please try the following: 1. As I cannot find any traffic to the router (192.168.0.254) in the netmon trace, please try to PING the router from the Windows Vista client and check how it works. Afterpingingsuccessfully, will you be able to access the Internet web sites? 2. On the problematic Windows Vista client, collect the "arp -a" output and check whether the router's MAC address is properly registered? Meanwhile, could you please provide us the MAC cache table from the router? Meanwhile, I would like to share the following document with you: TCP/IP Networking from the Wire Up Thanks. Nicholas Li - MSFT

HelloThe router address is 192.168.1.254.I have now replaced the router with a different manufacturer (not draytek) and the problem has gone, I'd previously replced a Draytek with a Draytek....different models but same manufacturer.Thanks you for your help, and the document.Many thanksJohnFidget

Hi, Thank you for writing back and letting us know the current situation. I am glad to know that the issue has been resolved by replacing the router. If you have any other questions or concerns, please do not hesitate to contact us. It is always our pleasure to be of assistance. Thanks again for your efforts. Have a nice day!Nicholas Li - MSFT