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Block and Unblock ICMP Messages

Applies To: Windows Server 2003, Windows Server 2003 R2, Windows Server 2003 with SP1, Windows Server 2003 with SP2

Use this procedure to block or unblock Internet Control Message Protocol (ICMP) messages. This procedure is useful if you want to allow other computers to access your computer with the ping command or tracert command.

Administrative Credentials

To perform this procedure, you must be a member of the Administrators group on the local computer, or you must have been delegated the appropriate authority. If the computer is joined to a domain, members of the Domain Admins group might be able to perform this procedure.

Special Considerations

You can configure Windows Firewall settings in the standard profile or the domain profile. The domain profile is used when a computer is connected to a network in which the computer's domain account resides. The standard profile is used when a computer is connected to a network in which the computer's domain account does not reside, such as a public network or the Internet. Make sure Windows Firewall is using the correct profile when you perform this procedure.

For more information about Windows Firewall profiles, see Managing Windows Firewall Profiles.

To block and unblock ICMP messages

This procedure can be performed using the graphical user interface or the command prompt.

Using the graphical user interface

To block and unblock ICMP messages

  1. Open Windows Firewall.

  2. Click the Advanced tab.

  3. In ICMP, click Settings.

  4. In the ICMP Settings dialog box, do one of the following:

    To unblock an ICMP message (allow the ICMP message to pass through Windows Firewall), select the check box next to the ICMP message and then click OK.

    To block an ICMP message (prevent the ICMP message from passing through Windows Firewall), clear the check box next to the ICMP message and then click OK.

If a Windows Firewall setting appears dimmed in the graphical user interface, and on the General tab, you see For your security, some settings are controlled by Group Policy, the setting might be managed by Group Policy. If all Windows Firewall settings appear dimmed, and on the General tab, you see You must be a computer administrator to change these settings, you do not have administrative rights to configure Windows Firewall.

Using the command prompt

To block and unblock ICMP messages

  • Type the following at the command prompt, and press ENTER:

    netsh firewall set icmpsetting type = type mode = mode

Substitute values for the placeholders in italics. The following table lists possible values for each placeholder.

Placeholder Possible Values Description

type

2,3,4,5,8,9,11,12,13,17, All

Specifies the ICMP message type. All specifies that you want to configure all ICMP message types.

mode

Enable, Disable

Specifies whether to enable (allow the ICMP message to pass through Windows Firewall) or disable (prevent the ICMP message from passing through Windows Firewall).

If you get an "Access Denied" message when you run a command, you do not have administrative rights to configure Windows Firewall. If you get an "Ok" message but the command does not take effect, the setting might be managed by Group Policy.

Notes

  • To start Windows Firewall, click Start, point to Control Panel, and then click Windows Firewall.

  • To open a command prompt, click Start, point to All programs, point to Accessories, and then click Command Prompt.

  • Windows Firewall is not included in the original release of the Windows Server 2003 operating systems.

See Also

Concepts

Known Issues for Managing IPsec, Multicast, and ICMP Settings
Configuring ICMP Settings