This article describes how to turn on or turn off the firewall in Windows XP Service Pack 2 (SP2) and Windows XP Service Pack 3 (SP3). You might want to disable the firewall if you want to troubleshoot applications that do not function as expected behind a firewall.

Note A firewall is software or hardware that checks information that comes from the Internet or from a network. The firewall either blocks the information or lets the information pass through to your computer. Whether information is blocked or passed through depends on your firewall settings. A firewall can help prevent malicious software (such as worms) from gaining access to your computer through a network or the Internet. A firewall can also help stop your computer from sending malicious software to other computers. Windows XP, Windows XP SP2, and Windows XP SP3 include firewall software.

Note These steps are only for Windows XP SP2 and Windows XP SP3. These steps are not for earlier versions of Windows XP. If you are not sure which version of Windows XP you are running, go to the "How to determine your current service pack" section.

To have us turn on the firewall for you, go to the "Fix it for me" section. If you’d rather do this yourself, go to the "Let me fix it myself" section.

Fix it for me

To turn on the firewall automatically, click the Fix this problem link, click Run in the File Download dialog box, and then follow the steps in this wizard.



Notes

• This wizard may be in English only. However, the automatic fix also works for other language versions of Windows.
• If you are not on the computer that has the problem, you can save the automatic fix to a flash drive or CD, and then you can run it on the computer that has the problem.

Let me fix it myself

To enable Windows Firewall, follow these steps:

1. Click Start, click Run, type Firewall.cpl, and then click OK.
2. On the General tab, click On (recommended).
3. Click OK.

Note If the General tab or the On (recommended) option is unavailable, the system may have a policy against running the firewall. Contact the system administrator for more information about how to enable the firewall. In addition, the system may already be running a third-party firewall (Zone Alarm or Norton Internet Security, for example). Contact the system administrator for help in determining whether a firewall is already running on the system.

If you still need assistance after you contact the system administrator, contact support.

Note These steps are only for Windows XP SP2 and Windows SP3. They are not for earlier versions of Windows XP. If you are not sure which version of Windows XP you are running, go to the "How to determine your current service pack" section.

Note When you turn off the firewall, you leave your computer vulnerable to attack. Therefore, before you turn off your firewall, disconnect your computer from all networks. This includes the Internet. Or, you can enable a third-party firewall.

To disable Windows Firewall, follow these steps:

1. Click Start, click Run, type Firewall.cpl, and then click OK.
2. On the General tab, click Off (not recommended).
3. Click OK.

Before you start a download of an updated Service Pack, you should determine which service pack you are currently running. To do this, click Start, click Run, type sysdm.cpl, and then click OK.

The last line under System tells you which service pack you are running. If no service pack is listed, you are running the release version of Windows XP.

Warning If you are running either the release version of Windows XP or Windows XP Service Pack 1 (SP1), the product is out of life cycle. Therefore, there is no update support that is available. In this case, you should update to Windows XP SP3 as soon as possible.

For more information about the latest Windows XP service pack, click the following article number to view the article in the Microsoft Knowledge Base:

For more information about the changes in Windows Firewall in Windows XP SP2, see the "New Networking Features in Windows XP Service Pack 2" article in the January 2004 "Cable Guy" column.

The third-party products that this article discusses are manufactured by companies that are independent of Microsoft. Microsoft makes no warranty, implied or otherwise, about the performance or reliability of these products.