This article is a consolidation of the following previously available articles: 312415 and 895857
Important This article contains information that shows you how to help lower security settings or how to turn off security features on a computer. You can make these changes to work around a specific problem. Before you make these changes, we recommend that you evaluate the risks that are associated with implementing this workaround in your particular environment. If you implement this workaround, take any appropriate additional steps to help protect your system.
WORKAROUND
Use one of the following workarounds, depending on which kind of firewall you are running.
If you are running PIX Software, Raptor Firewall, or Firewall-1
To permit the SMTP commands that you require to reach your Exchange computer, you must turn off the SMTP command filter.
Warning This workaround may make your computer or your network more vulnerable to attack by malicious users or by malicious software such as viruses. We do not recommend this workaround but are providing this information so that you can implement this workaround at your own discretion. Use this workaround at your own risk.
Note A firewall is designed to help protect your computer from attack by malicious users or by malicious software such as viruses that use unsolicited incoming network traffic to attack your computer. Before you disable your firewall, you must disconnect your computer from all networks and the Internet.
For more information about in which you cannot send or receive e-mail messages behind a Cisco PIX firewall, click the following article number to view the article in the Microsoft Knowledge Base:
320027
Cannot send or receive e-mail messages when you are behind a Cisco PIX firewall
For information about how to turn off the SMTP command filter on your firewall, contact the manufacturer of your firewall product.
For information about how to contact the manufacturer of your firewall product, click the appropriate article number in the following list to view the article in the Microsoft Knowledge Base:
65416 Hardware and software vendor contact information, A-K
60781 Hardware and software vendor contact information, L-P
60782 Hardware and software vendor contact information, Q-Z
For information about how to contact Check Point Software Technologies Ltd., visit the following Check Point Software Technologies Web site:
Microsoft provides third-party contact information to help you find technical support. This contact information may change without notice. Microsoft does not guarantee the accuracy of this third-party contact information.
If you are running Wingate Proxy/Firewall
To work around this issue, you must replace the Wingate Proxy/Firewall. For information about alternative firewall programs that may replace Wingate Proxy/Firewall, contact C&C Software Solutions. For information about how to contact C&C Software Solutions, visit the following C&C Software Solutions Web site:
Microsoft provides third-party contact information to help you find technical support. This contact information may change without notice. Microsoft does not guarantee the accuracy of this third-party contact information.
If you are running Firebox 1000 firewall
To work around this issue on a Firebox 1000 firewall, you must remove and then reinstall the SMTP proxy service. For more information about how to remove and then reinstall the SMTP proxy service on the Firebox 1000 firewall, contact WatchGuard Technologies, Inc. For information about how to contact WatchGuard Technologies, visit the following WatchGuard Technologies Web site:
Microsoft provides third-party contact information to help you find technical support. This contact information may change without notice. Microsoft does not guarantee the accuracy of this third-party contact information.
If you use the SMTP Proxy service on the WatchGuard Firebox to specify which message headers are included with a message
To work around this issue, disable the WatchGuard Firebox SMTP Proxy service. WatchGuard has a software update to correct this behavior. To obtain the update, contact WatchGuard support.
If you are running SonicWALL firewall
To work around this issue, configure the port on your router where the SonicWALL firewall is connected to 10 MB half duplex. For more information about how to configure your router, contact the manufacturer of your router.
For information about how to contact the manufacturer of your router, click the appropriate article number in the following list to view the article in the Microsoft Knowledge Base:
65416 Hardware and software vendor contact information, A-K
60781 Hardware and software vendor contact information, L-P
60782 Hardware and software vendor contact information, Q-Z
Microsoft provides third-party contact information to help you find technical support. This contact information may change without notice. Microsoft does not guarantee the accuracy of this third-party contact information.
If you set the maximum message size on a firewall
To work around this issue, turn off or increase the maximum message size setting on the firewall. For more information, contact the manufacturer of your firewall.
For information about how to contact the manufacturer of your firewall, click the appropriate article number in the following list to view the article in the Microsoft Knowledge Base:
65416 Hardware and software vendor contact information, A-K
60781 Hardware and software vendor contact information, L-P
60782 Hardware and software vendor contact information, Q-Z