A Windows Server 2003-based computer responds slowly to RDP connections or to SMB connections that are made from a Windows Vista-based computer

Consider the following scenario:

• You have installed Windows Server 2003 Service Pack 2 (SP2) or the Windows Server 2003 Scalable Networking Pack (SNP) on a Windows Server 2003-based computer.
• The EnableTCPA registry entry is set to 1 under the following registry subkey:
  HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\Tcpip\Parameters
• Network driver interface specification (NDIS) 5.2 miniports are installed on the computer.
• Firewalls and IPsec are not enabled in Windows Server 2003.

In this scenario, the Windows Server 2003-based computer responds slowly to Remote Desktop Protocol (RDP) connections or to server message block (SMB) connections that are made from a Windows Vista-based computer. For example, when you copy files from a Windows Vista-based computer to a Windows Server 2003-based computer, the copying speed is very slow.

A hotfix is now available to resolve this problem. For more information about how to obtain the hotfix, click the following article number to view the article in the Microsoft Knowledge Base:

Workaround 1

Disable the TCP autotuning feature on the Windows Vista-based computer. To do this, follow these steps:

1. Log on to the computer as a user who has administrative credentials.
2. Click Start, type runas /user:Local_Computer_Name\administrator cmd in the Start Search box, and then press ENTER.
3. When you are prompted for the administrator account password, type the correct password, and then press ENTER.
4. Type the following command at the command prompt, and then press ENTER:
   netsh interface tcp set global autotuninglevel=disabled
5. Exit the command prompt.
6. Restart the computer.

Workaround 2

Important This section, method, or task contains steps that tell you how to modify the registry. However, serious problems might occur if you modify the registry incorrectly. Therefore, make sure that you follow these steps carefully. For added protection, back up the registry before you modify it. Then, you can restore the registry if a problem occurs. For more information about how to back up and restore the registry, click the following article number to view the article in the Microsoft Knowledge Base: Set the EnableTCPA registry entry to 0 on the Windows Server 2003-based computer. To do this, follow these steps:

1. Click Start, click Run, type regedit, and then click OK.
2. Locate the EnableTCPA registry entry under the following registry subkey:
   HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\Tcpip\Parameters
3. Right-click EnableTCPA, and then click Modify.
4. In the Value data box, type 0, and then click OK.
5. Exit Registry Editor.

Workaround 3

Enable firewalls or IPsec on the network interface of the Windows Server 2003-based computer.

Microsoft has confirmed that this is a problem in the Microsoft products that are listed in the "Applies to" section.