I'm using Windows 7 Pro on an M90 ThinkCentre that was previously running XP Pro. This is running on a 2003 domain that has other (all working fine) Windows 7 and XP Pro installations. This system worked fine when XP Pro was installed. After installing 7, the system will connect and a user can log on to the domain, but the network connectivity seems to have its own mind about how to work. The computer is using DHCP and has only the default Windows firewall rules installed (disabled or enabled make no difference in functionality). DNS works for internal and external targets, but if I try to open a IE to www.google.com it takes about 5-6 minutes to load the splash page. This works instantly on the computer adjacent to it, plugged into the same physical switch (even tried swapping cables in a last ditch effort before coming here). Connections to other domain computer will work (including mapping drives), but listing the contents of folders is unusually slow (compared to normal operations). When I try to copy a file off the network (~300mb) to install a program and the copy will appear to begin, the dialog sits at "calculating" for a few minutes before indicating that its about to start copying, and then will continue to sit at 0 bytes until it inevitably fails. The error will usually be "Make sure you are connected to the network and try again". It's important to note that the network icon in the tray does not at any point indicate the computer looses network connectivity. In advanced sharing settings the follow settings are configured: -Turn on network discovery -Turn on file and printer sharing -Turn off Public folder sharing -both 128bit and 40/56bit encryption have been attempted While watching Resource Monitor and trying to get an idea of what is happening and it's clear that programs are trying to connect but the activity is almost nonexistent. Iexplore.exe will open a connection that will sit at 0 bytes for the better part of a minute before finally trickling up to double digit bytes (eventually closing once google.com fully appears). I have tried both a clean image from retail CD's and the manufacturers recovery CD's, both resulting in the same issue I'm inclined to beleive this is somehow related to hardware, but knowing that the machine worked fine on XP Pro tells me it can only be software. Other identical model systems (shipped with Win 7) work on the network and have zero issues. Pinging localhost results in no lost packets, but pinging the adjacent Windows 7 computer will result in about 1/10 packets being lost (randomly, sometimes up to 5 in succession). I have done some searching through existing threads about changing network card settings, IPv4 offload, etc. and none of these have resulted in any changes. I am thoroughly out of ideas. Happy to provide additional logs or information if you'll just tell me where to get them. Thanks in advance,

Hi, According to your description, I suggest to perform these tests to make it fast on Windows 7 network: 1 Disable Autotuning: Open CMD as administrator, and input the command: Netsh interface tcp set global autotuning=disabled 2 Disable remote differential compression: Open Programs and Features, remove the feature “Remote Different Compression” 3 Temporally disable IPv6 4 Clear DNS Cache: Ipconfig /flushdns 5 Modify link speed and duplex value in network adapter properties: Right click network adapter and choose properties, go to advanced tab, choose link speed& Duplex, select the value to “Auto Negotiation” Hope that helps. Regards, Leo HuangPlease remember to click Mark as Answer on the post that helps you, and to click Unmark as Answer if a marked post does not actually answer your question. This can be beneficial to other community members reading the thread.