Troubleshoot Vista Network Problems

	This article describes why an outdated network router may not function correctly when you use it together with new networking features in Windows Vista. When you use an older router together with Windows Vista, you may experience any of the following problems: Slow network connection speeds or Internet connection speeds Gradual loss of network performance Lack of support for new features or for networking technologies Page errors occur when you surf the Internet The network router may stop functioning, and you must reset the router

	Consider the following scenario: You are using a Windows Vista-based computer that has two network adapters. Only one of the network adapters is connected. You do one of the following: You set up Windows Media Player 11 by using the Welcome to Windows Media Player 11 for Vista Wizard, and select the Express Settings (recommended) setting. You install third-party software, such as a CD burning program or a DVD burning program, or you install a program that plays DVDs. "To work around this problem, ...ignore the red 'X'"
	After you log on to Windows Vista by using the Guest account, the network icon in the notification area indicates that the network is either disabled or disconnected. Additionally, you may receive the following error message: Connection status: unknown. The service to detect this status is turned off.
	A wireless network uses authentication and encryption to help stay secure. Authentication controls access to the wireless network. Encryption helps make sure that malicious users cannot determine the contents of wireless data frames. Windows Vista includes a new wireless network configuration setting. The new setting indicates whether a wireless network is broadcast or non-broadcast. You can also use the new setting to configure how a Windows Vista wireless client connects to a non-broadcast network.
	You establish a virtual private networking (VPN) connection to the corporate network from a computer that is running Windows Vista. When you try to access network resources, you experience the following symptoms: You cannot access network resources. Domain name resolution is not successful.

	On a Windows Vista-based computer that is using an 802.11n wireless network adapter, you pause the pointer over the network connection in the Connect to a network dialog box. Then, you receive a message that resembles the following: Radio Type: 802.11g The message suggests that the computer is using an 802.11g wireless network adapter instead of an 802.11n wireless network adapter.
	You are running Windows Vista on a mobile PC. When you open the Windows Mobility Center item in Control Panel, you notice that the Wireless Network tile is not displayed.
	Earlier Windows operating system, such Windows XP and Windows Server 2003, provide support for IP networking over the IEEE 1394 bus. The supported networking interface is listed in the Network Connections folder as 1394 Connection. However, in Windows Vista and in later versions of Windows, Microsoft has discontinued support for IP networking over the IEEE 1394 bus.
	In some scenarios, the Network Discovery and File Sharing dialog box may be unexpectedly minimized to the taskbar in Windows Vista. The Network Discovery and File Sharing dialog box may contain prompts that affect how files and folders are shared on the computer. For example, the Network Discovery and File Sharing dialog box may be waiting for an answer to a prompt. However, you may not notice the prompt immediately because it is minimized. Therefore, you may unnecessarily wait for the prompt because the dialog box is minimized. In some scenarios, a sharing progress bar may appear on the screen. However, the progress bar never finishes.
	When you create a network connection that automatically calls another connection in Windows Vista, incorrect credentials appear when Windows Vista tests the connection. When Windows Vista tests the connection, incorrect credentials appear in the User name box and Password box of the network connection on which the double-dial connection depends. You expect the credentials that you saved for the initial network connection or for the Internet connection to appear in the User name box and Password box of the initial network connection or of the Internet connection. However, the credentials that you configured for the double-dial connection, such as for a virtual private network (VPN) connection, appear instead.
	This article describes how to connect to a wireless network in Windows Vista.
	After you wake a Windows Vista-based computer from sleep or from hibernation, you experience the following symptoms: The network icon in the notification area at the far right of the taskbar is not updated to show the connectivity status of the computer. If you connect a network cable to the computer or if you connect to a wireless network, the network icon in the notification area incorrectly shows the connectivity status as disconnected. If you move the pointer over the network icon in the notification area, the Currently connected to ScreenTip does not appear as expected. If you click the network icon in the notification area, the Currently connected to ScreenTip does not appear as expected. You experience these symptoms even though you can successfully connect both to wired networks and to wireless networks.

	Remote Procedure Call-based operations may fail if certain firewall and VPN products deny network requests. This denial occurs if the network requests come from Microsoft Windows Server 2003 Service Pack 1-based or Windows Vista-based computers. These network requests may fail on computers where you apply Windows Server 2003 Service Pack 1 (SP1) to a Windows Server 2003-based computer or your OEM or retail installation media includes SP1 updates. The following products may deny these network requests: Firewall or virtual private network (VPN) products from Checkpoint Software Technologies Microsoft Internet Security and Acceleration (ISA) Server Cisco VPN Client 5.0.0.0340
	On a computer that is running Windows Vista, you intermittently lose access to network resources if more than one Network Device Interface Specification (NDIS) filter driver is installed.
	Consider the following scenario: You use the Windows Vista Get Connected Wizard to connect a Windows Vista-based computer to a destination network. The user name and password that is configured in the network connection is saved for all users. For example, when you create the network connection, you click to select the Allow other people to use this connection check box. The password for the network connection expires on the destination network. In this scenario, when you next use this connection to connect to the destination network, you are prompted to change the password as expected. However, when you enter a new password for the network connection, you experience the following symptoms: You receive the following error message: Cannot delete saved password. Error 5: Access is denied. The new password is updated on the destination network. However, the new password is not saved in Windows Vista. Therefore, you must enter the new password again when you try to reconnect to the destination network.
	When you use the Netsh command-line scripting utility (Netsh.exe) to modify the network configuration, the command is not executed. Then, you receive an error message in Windows Vista. For example, you type the following command at a command prompt: Netsh interface set interface "Local Area Connection 2" enable Then, you receive one of the following error messages: An interface with this name is not registered with the router No more data is available
	After you uninstall a network adapter in the Device Manager on a Windows Vista-based computer, you receive the following message in the notification area at the far right of the taskbar: Installing device driver software Then, the network adapter is automatically reinstalled.
	When the IP address configuration changes from an alternate IP address to a static IP address in Windows Vista, both the alternate IP address and the static IP address remain on the network interface.
	In Windows Vista, after you create a subfolder in a shared folder on a network, you receive the following error message when you try to rename the new subfolder: The SharedFolderName folder does not exist. The file may have been moved or deleted. Do you want to create it? The message incorrectly states that the shared folder does not exist. Additionally, if you save a file to the shared folder on a network, you may receive the following error message: There has been a network or file permission error. The network connection may be lost.
	When you use a wireless connection for network connectivity on a Windows Vista-based computer, you may receive the following message for a device in the Connect to a network dialog box: Connected with limited access This problem occurs if a device on the Windows Vista-based computer uses a network bridge to access the network. You may also receive the following error message: Connection unsuccessful - If you are connecting to a wireless hotspot, you might need to open a web browser to finish connecting. You receive these messages even though the device has good network connectivity using the wireless network bridge.
	In Windows Vista and in Windows XP, photos that are located on a network may be missing from Windows Photo Gallery or from Windows Live Photo Gallery. When you restart Windows Photo Gallery or Windows Live Photo Gallery, the program stops responding.
	In Windows Vista, the TCP/IPv4 default gateway address is deleted when you use the Netsh command-line tool to configure the network interface IP address for the Dynamic Host Configuration Protocol (DHCP). For example, you type the following command at a command prompt: netsh interface ipv4 set address name="Local Area Connection" source=dhcp If you check the default gateway address by using the ipconfig command, you see that the IPv4 default gateway address is deleted.
	You have a Windows Vista-based computer that is connected to the home network through a Gigabit Ethernet switch. When you use Windows Media Center Extender features on the computer, you experience one or more of the following symptoms: Poor video quality Slow performance Video content does not play
	On a Windows Vista-based computer, consider the following scenario: You use Wi-Fi Protected Access (WPA) together with Advanced Encryption Standard (AES) encryption to access wireless networks. A computer certificate is configured correctly on the computer. The computer has the correct permissions to access wireless networks. In this scenario, you can see that a wireless network is available in the Connect to a network dialog box in the Network and Sharing Center. However, you cannot connect to the wireless network.
	Five minutes after you log on to a Windows Vista-based computer, 802.1X network authentication times out, and authentication fails. Therefore, network connectivity is not established. You are not prompted to log on to a wired 802.1X network during the five-minute period after you log on.
	After you turn on User Account Control in Windows Vista, programs may be unable to access some network locations. This problem may also occur when you use the command prompt to access a network location.
	You start or run a network-capable program in Windows Vista. Then, the program stops unexpectedly (crashes) in either of the following cases: When the program tries to read valid data from a remote storage medium. When the program tries to write valid data to a remote storage medium. Additionally, you receive an error message that resembles the following: Program_name has caused an error and must be closed. We apologize for the inconvenience. If you were in the middle of something, the information you were working on might be lost. Please tell Microsoft about this problem. We have created an error report that you can send to help us improve Program_name. We will treat this report as confidential and anonymous. To see what data this error report contains, click here.
	The Windows Dynamic Host Configuration Protocol (DHCP) server provides a "Vendor class" option that you can use to disable NetBIOS over TCP/IP on the DHCP client. This article describes how to do this.
	On a Microsoft Windows Vista-based computer, you may experience one or more of the following symptoms in a wireless network environment: Symptom 1 IEEE 802.1X authentication that is based on Virtual Local Area Network (VLAN) switching may fail. For example, you try to use computer authentication and user authentication to switch the client computer to different VLANs. However, the client computer does not obtain the correct IP address during VLAN switching. Symptom 2 In a wireless profile, the information about the Extensible Authentication Protocol (EAP) method that is selected in a user interface may be incorrect. For example, if different vendors provide more than one EAP method, the EAP method that is displayed in a wireless profile is not the EAP method that is actually selected. Symptom 3 A wireless profile that an independent hardware vendor (IHV) provides may be corrupted after you use the wireless profile user interface to edit the profile. When this problem occurs, you may receive an error message that Windows Explorer has crashed. Symptom 4 Every time that you roam to a different wireless access point, you are prompted to provide a user credential. This problem occurs even if you have saved the user credential. Symptom 5 You registered a Protected Extensible Authentication Protocol (PEAP) method that the IHV provided. When you try to authenticate against an Internet Authentication Service (IAS) server, the server may reject the authentication, and the IAS server may send an error message that the authentication has failed. The Onex.dll file crashes when this problem occurs.
	When you install a software that adds legacy network drivers on a computer that is running Windows Vista, Windows Vista may stop responding.
	Consider the following scenario. You switch a network connection from one network adapter to another network adapter. Then, you dial a virtual private network (VPN) connection to the remote VPN server. You can successfully establish the connection to the remote VPN server. However, you cannot access any resources on the remote VPN server.
	In the properties dialog box for a network adapter, the TCP/IP Version 4 (TCP/IPv4) protocol appears to be enabled even when it is disabled. The Internet Protocol Version 4 (TCP/IPv4) check box is selected.
	Consider the following scenarios: You upgrade a Windows XP-based computer to Windows Vista. You upgrade a pre-release version of Windows Vista to the release version of Windows Vista. You upgrade a release version of one Windows Vista operating system to another release version of Windows Vista. In any one of these scenarios, third-party network-related programs may no longer function. You experience this issue with programs such as virtual private network (VPN) programs or load balancing and failover (LBFO) programs.
	You may experience random connectivity issues when you connect a Windows Vista-based mobile PC to certain Wi-Fi "hot spots." These connectivity issues include the following: The wireless network connection is dropped. You experience poor performance. You experience these issues if the Windows Vista-based computer is running on battery power. Note You may also experience these issues when you connect a Windows Vista-based mobile PC to a wireless access point (AP) in a small office/home office (SOHO) environment or in an enterprise environment.
	When you use a network connection to copy a large file from one Windows Vista-based computer to another Windows Vista-based computer, you may receive an error message that resembles one of the following: Error message 1 The connection has been lost. Error message 2 There is a problem accessing shared folder path. Make sure you are connected to the network and try again. This problem may occur if the following conditions are true: The network connection is slow or is prone to errors. For example, the network connection uses long-distance, slow-wired links or modems. Or, the network connection uses a wireless 802.11 or Bluetooth connection, and the network signal is weak. For example, the wireless network signal may be weak because of the distance from the access point or because of interference. The problem may also be affected by network traffic, by network retries, by packet losses, or by other factors that affect reliability of the connection. The file that is being transferred is large. For example, the possibility of experiencing this problem is proportional to the size of the file that is being copied. For example, you may experience the problem when the file is approximately 100 megabytes (MB) or larger on an 802.11b 11 Mbps wireless network.
	When you try to use a Windows Vista-based computer behind a firewall device, network connectivity may fail. When network connectivity fails, you may see the following symptoms: Programs may respond slowly. Programs may stop responding. For example, any of the following programs may be affected by this problem: Microsoft Outlook or Windows Mail A Web browser, such as Windows Internet Explorer 7 Remote Desktop Connection (RDC) File sharing
	When you try to connect a Windows Vista-based computer to a network printer whose name is not a valid Universal Naming Convention (UNC) path, the connection fails. This problem affects some third-party printers. If a third-party printer provider does not use a UNC path to name a printer, you cannot connect the computer to the printer.
	After you configure Internet Connection Sharing in Windows Vista, you may find that, although the network connection works correctly at first, the network connection stops working after one-to-two hours. For example, you may be unable to connect to the Internet, to other computers on the local area network (LAN), or to network resources on the LAN.
	When you wake a Windows Vista-based computer from sleep or from hibernation, a dial-up connection may appear to be still connected to the Internet even though the connection is not active. When this problem occurs, the Network Center correctly shows that the dial-up connection is inactive. This problem may occur on some computers if you put the computer to sleep or into hibernation when the dial-up connection is still connected to the Internet, and then you wake the computer. In this scenario, the network icon in the notification area may indicate that the connection is active. However, the dial-up connection does not work. This problem can occur in some hardware configurations if the computer uses an external modem or a PCMCIA modem for the dial-up connection.
	When the GUID of a network adapter changes on a client computer that is running Windows Vista, the computer registers an old IP address that was associated with the old GUID. The client computer also registers new IP addresses that are associated with the new GUID. However, because the client computer registers old IP addresses, another client computer may try to use the old IP address. If the old address is not valid, a connection failure may occur.
	On a Windows Vista-based computer, you try to connect to a network by using a dial-up connection in Windows Internet Explorer 7. However, you may receive an error message that resembles the following: Cannot write to the telephone book. Error 624 : Telephone book file cannot be updated. The dial-up connection attempt is unsuccessful.
	On a Windows Vista-based computer, when you try to copy files from a server on a network, the copy process may stop responding (hang), and you may receive a message that resembles the following: Calculating Time Remaining 0 minutes remaining This problem may occur only occasionally.
	You cannot access a shared network resource that is hosted by a Windows Vista-based computer if one of the following conditions is true: The size of the server message block (SMB) request packet exceeds the maximum transmission unit (MTU) size of the requesting device. The size of the SMB request packet exceeds the MTU size of the router that connects the requesting device with the server
	Consider the following scenario: On a Windows Vista-based computer, you copy files to or from another computer on a network. This other computer is a Microsoft Windows XP-based computer or a Microsoft Windows Server 2003-based computer. These files are each 100 megabytes (MB) or larger. You use Windows Explorer to copy the files. For example, you use a drag-and-drop operation in Windows Explorer to copy the files. In this scenario, the file transfer operation may be slightly slower than expected. This problem occurs only in certain hardware configurations. This problem does not occur when you copy files to or from another Windows Vista-based computer.
	Consider the following scenario. You use a local area network (WLAN) device on a computer that is running Windows Vista ("Computer A") to establish a computer-to-computer (ad hoc) connection that has WPA2 specified. You have another Windows Vista-based computer ("Computer B") that also has a wireless adapter installed. In this scenario, when you try to establish an ad hoc connection from Computer B, you may receive the following error message: Windows cannot connect to (Network Name) Note: In this error message, (Network Name) is a placeholder for the name of the ad hoc connection.
	When you configure a wireless connection in Windows Vista, the Service Set Identifier (SSID) information may display the wireless profile name instead of the actual SSID.
	After you use Windows Vista to change the name of a computer, other computers can continue to access the computer by using the previous name of the computer. When this issue occurs, the following conditions are true: If you clear the Domain Name System (DNS) cache by using the ipconfig command together with the /flushdns switch, this issue still occurs. If you change the network adapter at the same time that you change the name of the computer, this issue does not occur.
	You transfer a file between a Windows Vista-based client computer and a file server that is running a previous Windows operating system. Then, the Windows Vista-based client stops responding. This problem occurs if the following conditions are true: Windows Vista and the file server use the Server Message Block (SMB) 1.0 protocol to transfer the file. The network connection between the Windows Vista-based client computer and the file server is lost when you transfer the file. For example, the network cable is unplugged when you transfer the file.
	On a Windows Vista-based computer, when you try to communicate with another computer through an Internet Protocol security (IPsec) tunnel-mode connection, the connection fails. This issue occurs if the Windows Vista-based computer is behind a Network Address Translation (NAT) device.
	Consider the following scenario: On a Windows Vista-based computer, you establish a dial-up connection to connect to the Internet. You establish a virtual private network (VPN) connection through a dial-up connection. In this scenario, the VPN credentials are not cached the first time that the VPN connection is established.
	Consider the following scenario: You work with a Windows Vista-based computer that is a member of a workgroup. On this computer, you try to access an administrative share that is located on another Windows Vista-based computer. The computer that you try to access is a member of a workgroup or a member of a domain. For example, you try to access the C$ administrative share. When you are prompted for your user credentials, you provide the user credentials of an administrative user account on the destination computer. In this scenario, you receive the following error message: Logon unsuccessful: Windows is unable to log you on. Make sure that your user name and password are correct. If you try to map a network drive to the administrative share by using the Net Use command, you receive the following error message after you provide the correct credentials: System error 5 has occurred. Access is denied.
	Consider the following scenario: You connect a Windows Vista-based computer to a network. A router or other device that is configured as a Dynamic Host Configuration Protocol (DHCP) server is configured on the network. The router or the other device does not support the DHCP BROADCAST flag. In this scenario, Windows Vista cannot obtain an IP address.
	When you wake a Windows Vista-based computer from sleep, the default gateway setting is lost. When you run the ipconfig /all command to view the IP configuration, you cannot see the default gateway setting. This problem occurs if the following conditions are true: The computer is configured as a Dynamic Host Configuration Protocol (DHCP) client, and the computer is connected to a DHCP server. The DHCP server configures a scope together with options 3 and 249. The computer is included in this scope.
	Consider the following scenario: You have a Windows Vista-based computer that is running Windows Firewall. A client application tries to connect through TCP port 1723. In this scenario, Windows Vista may disconnect communications to the client. The following are examples of such client applications: FTP applications that connect through port 1723 P2P applications that connect through port 1723 Multifunction printers on which scanning or faxing options use port 1723 for communications