What is the problem?
Slow network performance under Windows Server 2008*.
What is the cause?
Windows Server 2008* uses TCP window scaling to maximize network performance. Older routers, firewalls, and operating systems not compatible with this feature might see slow data transfer or loss of connectivity.
If the issue only happens with Hyper-V, see Low network performance observed with Windows 2008 R2*
How to fix it:
- Make sure your router, firewall, and client operating system support TCP window scaling.
- Check with the network device manufacturer for firmware updates that support TCP window scaling.
- If the issue continues, disable TCP window scaling on Windows Server 2008* by running this command:
netsh interface tcp set global autotuninglevel=disabled
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