When you try to send and receive e-mail, you may receive an error message that is similar to one of the following:You may also receive an error message that includes one or more of the following error codes:

•	0x800ccc15
•	0x80042108
•	0x800ccc0e
•	0x8004210b
•	0x800ccc0b
•	0x800ccc79
•	0x800ccc67
•	0x80040900
•	0x800ccc81

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These error messages may occur if Microsoft Outlook or if Microsoft Outlook Express cannot establish a connection with your e-mail server. These error messages are frequently caused by one of the following:

•	You are not connected to the Internet or a network
•	Incorrect account settings
•	Your user profile in Outlook is damaged
•	An e-mail item on your POP3 server is damaged
•	Incorrect configuration of your AV software
•	Outlook Express has been removed from the computer or the installation is damaged
•	Incorrect configuration of personal firewall software

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The most common causes of these error messages are problems with Internet connectivity and incorrectly configured account settings in Outlook or Outlook Express. First, verify you are connected to the Internet. To do this, follow these steps:

Step 1: Verify that you are connected to the Internet

To verify Internet connectivity, follow these steps:

1.	Start an Internet browser, such as Internet Explorer
2.	Type one of the following addresses in the address bar • http://www.microsoft.com • http://www.msn.com • http://www.live.com

If you continue to experience network connectivity problems when you type one of these addresses in the Address bar, view the following article for more information about how to troubleshoot Internet connectivity problems:If you can successfully connect to the Internet, the next step is to verify your e-mail account settings in Outlook or Outlook Express.

Step 2: Verify your account settings

To verify your e-mail account information and e-mail server settings are configured correctly in Outlook or Outlook Express, we recommend that you contact your E-mail service provider (which may also be your Internet Service provider).



For information about what settings should be checked in Outlook, view the following article in the Microsoft Knowledge Base: For information about what settings should be checked in Outlook Express 6.0, view the following article in the Microsoft Knowledge Base:

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Advanced Troubleshooting

If you are still experiencing problems sending and receiving mail after you have verified your e-mail server settings with your e-mail service provider, the following steps provide advanced troubleshooting steps. If you are not comfortable with advanced troubleshooting, you might want to ask someone for help or contact support. For information about how to do this, visit the following Microsoft Web site: Perform the following methods in order. If one method does not solve the issue, move on to the next one. .

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Method 1: Start Outlook in safe mode

To start Outlook in safe mode:

Windows Vista

1.	Click Start, type outlook.exe /safe in the Start Search box, and then press Enter

Windows XP, Windows Server 2003, or Windows 2000

1.	Click Start, and then click Run.
2.	In the Open box, type outlook.exe /safe , and then click OK.

Starting Outlook in safe mode starts Outlook without extensions, the preview pane, or toolbar customizations and could indicate a damaged profile or conflicting third-party application or add-in. See method 2 to create a new e-mail profile. To obtain help in identifying a conflicting application or add-in, you may want to contact support.

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Method 2: Create a new e-mail profile

You may be able to resolve these problems by creating a new e-mail profile. For more information about how to create profiles in Outlook, click the following article numbers to view the articles in the Microsoft Knowledge Base:

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Method 3: Delete suspicious messages from your mailbox

If there is a damaged message in your mailbox, you can resolve this by doing one of the following:

•	Contact your ISP and ask them to delete any suspicious e-mail.
•	Delete any suspicious e-mail by accessing your mailbox by using your ISP's Web-based e-mail program.

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Method 4: Check your antivirus vendor's Web site for additional suggestions

If your antivirus solution includes an e-mail scanning feature, you may have to do additional configuration to use Outlook or Outlook Express with the antivirus e-mail scanning feature.

Antivirus software that has been known to cause this problem includes products by the following vendors:

•	Symantec (Norton)
•	McAfee
•	Trend Micro (PC-cillin)
•	Panda

For more information, visit the following Web sites:

Symantec: McAfee: Trend Micro: Panda: Note An antivirus program is designed to help protect your computer from viruses. You must not download or open files from sources that you do not trust, visit Web sites that you do not trust, or open e-mail attachments when your antivirus program is disabled.

For more information about computer viruses, click the following article number to view the article in the Microsoft Knowledge Base: 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.
The third-party products that this article discusses are manufactured by companies that are independent of Microsoft. Microsoft makes no warranty, implied or otherwise, regarding the performance or reliability of these products. .

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Method 5: Remove and then reinstall Outlook Express

If Outlook Express has been removed from your computer or the installation of Outlook Express is damaged, Outlook will not function correctly and may generate one of the error messages that are mentioned in the "Symptoms" section. To resolve this problem, reinstall Outlook Express.

For more information, click the following article numbers to view the articles in the Microsoft Knowledge Base: For more information explaining why Outlook Express is required to use Outlook, click the following article number to view the article in the Microsoft Knowledge Base:

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Method 6: Verify that all SMTP e-mail addresses in a distribution list are valid

If one SMTP address in a distribution list is corrupted or incorrectly formed, error 0x8004210b can occur. Examine all addresses in the distribution list to verify that they look correct. Additionally, you can send individual test messages to each distribution list member to determine the bad address.

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Method 7: Examine the configuration of your firewall software

Warning This workaround may make a computer or a 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.

Important These steps may increase your security risk. These steps may also make the computer or the network more vulnerable to attack by malicious users or by malicious software such as viruses. We recommend the process that this article describes to enable programs to operate as they are designed to or to implement specific program capabilities. Before you make these changes, we recommend that you evaluate the risks that are associated with implementing this process in your particular environment. If you decide to implement this process, take any appropriate additional steps to help protect the system. We recommend that you use this process only if you really require this process.

Configure your firewall software to grant access to the Internet for the following files:

•	For Outlook Express: Msimn.exe
•	For Outlook: Outlook.exe

By default, most e-mail clients have to have outgoing access on port 25 and incoming access on port 110. For more information about the ports that communicate with your e-mail server, contact your ISP or system administrator.

Firewall software that has been known to cause this problem includes products by the following vendors:

•	McAfee
•	Symantec
•	ZoneLabs
•	Cisco
•	Sygate
•	Sonicwall
•	Freedom Security Zero Knowledge

McAfee Personal Firewall

Check your configuration settings in the McAfee Personal Firewall program and make sure that Microsoft Outlook or Microsoft Outlook Express has full access.

For more information about how to configure McAfee Personal Firewall, visit the following McAfee Web site: Alternatively, you can remove and reinstall the McAfee Personal Firewall program. The reinstallation process recreates the program signature file that is used by the firewall. Additionally, this process makes sure that both Outlook and Outlook Express are included in the list of programs where Internet access is permitted.

Norton Personal Firewall (Symantec)

If you are running Norton Personal Firewall 2002, Norton Internet Security, or Norton SystemWorks software by Symantec, contact Symantec product support for upgrade or reconfiguration instruction to resolve your problem.

For more information about how to contact Symantec, view the Symantec contact information described later in this article.

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If the error code is accompanied by a time-out error message, you may be able to resolve this problem by increasing the server time-out setting in Outlook or in Outlook Express. To increase the server time-out setting, use one of the following methods.

Outlook 2000 (CW)

1.	Start Outlook.
2.	On the Tools menu, click Services.
3.	On the Services tab, select Internet E-mail, and then click Properties.
4.	Click the Advanced tab.
5.	Gradually increase the server time-out setting until the problem is resolved.

Outlook 2000 (IMO)

1.	Start Outlook.
2.	On the Tools menu, click Accounts.
3.	Select the target account, and then click Properties.
4.	Click the Advanced tab.
5.	Gradually increase the server time-out setting until the problem is resolved.

Outlook 2002 and Outlook 2003

1.	Start Outlook.
2.	On the Tools menu, click E-mail Accounts.
3.	Click View or change existing e-mail accounts, and then click Next.
4.	Click your POP3 account, and then click Change.
5.	Click More Settings.
6.	Click the Advanced tab.
7.	Gradually increase the server time-out setting until the issue is resolved.

Outlook 2007

1.	Start Outlook.
2.	On the Tools menu, click Account Settings.
3.	Click to select the target POP3 account, and then click Change.
4.	Click More Settings.
5.	Click the Advanced tab.
6.	Gradually increase the server time-out setting until the issue is resolved.

Outlook Express 5.x and 6.0

1.	Start Outlook Express.
2.	On the Tools menu, click Accounts.
3.	Click the Mail tab.
4.	Click your POP3 account, and then click Properties.
5.	Click the Advanced tab.
6.	Gradually increase the server time-out setting until the problem is resolved.

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.

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