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How to solve common ActiveSync error messages

Discover how to fix common Exchange ActiveSync errors, including SSL Event ID errors 3029, 3030 and 30031, HTTP, SMTP and 0x80830003 synchronization errors.

Microsoft Exchange ActiveSync generally manages mobile devices without many problems. But when something goes wrong,...

resulting error messages can be puzzling. This troubleshooting guide highlights common Exchange ActiveSync errors, their causes and workarounds to solve each error. Find out how to fix HTTP_500 and SMTP problems, SSL Event ID errors 3029, 3030 and 3031, as well as the prevalent 0x80830003 synchronization failed error.


The HTTP_500 error message isn't unique to Exchange Server or ActiveSync. This particular error code usually is associated with Internet Information Server (IIS), and often occurs when coding Web pages using Active Server Pages (ASP). Typically, the error indicates that there is a breakdown of logic: the Web page's syntax is correct, but the code on the page is asking IIS to do something illogical or unrecognizable. From an ActiveSync standpoint, this error means nearly the same thing.

Fortunately, while HTTP_500 errors can be difficult to troubleshoot in an IIS environment, causes of these errors in ActiveSync are well documented. Typically, if you receive an HTTP_500 error, the actual error text appears as such:

Error code: HTTP_500
Synchronization failed due to an error on the server. Try again.

There are two main causes of this error:

  • A user has multiple SMTP addresses
  • The primary SMTP address doesn't match the default recipient policy

In Exchange Server 2003, you can correct this problem by installing Service Pack 2 (SP2). If this installation isn't an option, you can modify the server's registry. For the following workaround to succeed, your server must be running Exchange Server 2003 Service Pack 1 (SP1).

Keep in mind that editing the registry can be dangerous. If you make an incorrect registry modification, you can destroy Windows and/or Exchange Server. I strongly recommend that you administer a full system backup before implementing this change.

  1. Open the Registry Editor and navigate through the console tree to: HKEY_LOCAL_MACHINE\System\CurrentControlSet\Services\MasSync\Parameters.
  2. The Parameters container should be empty by default, but you must add a value to this container. To do so right click on the Parameters container and choose New -> String Value commands from the menu.
  3. Assign the name SMTPProxy to the new value. Keep in mind that the registry is case-sensitive.
  4. Right click on the value that you just created and choose Modify from the menu.
  5. When prompted to enter string data, enter the problematic SMTP domain name in ActiveSync. For example, if your organization's primary SMTP domain is, but ActiveSync is having problems with a secondary domain named In this case, enter as the data for the new SMTPProxy value.
  6. Click OK, and navigate through the registry tree to: HKEY_LOCAL_MACHINE\CurrentControlSet\Services\MSExchangeWEB\OWA.
  7. With the OWA container selected, look for the value: DisableSMTPMailboxAddressing If this value exists, you must disable it by right clicking on the value and choosing Modify from the menu. Then set the data value to 0.
  8. Close the Registry Editor and restart the IIS Admin Service by opening the Service Control Manager, and right clicking on the IIS Admin Service. Then select Restart.

0x8083003 ActiveSync error

Another common Exchange ActiveSync error involves the following message:

Synchronization failed. If the problem continues, contact your network administrator. Error code: 0x80830003

This problem occurs when you synchronize a mobile device on a computer Internet Security and Acceleration (ISA) Server 2000 Feature Pack 1. This problem shouldn't occur in a real-world situation because the ISA Server is intended as enterprise-level firewall and proxy solution. Therefore, it shouldn't be used as a personal workstation for mobile device synchronization. In the real world though, various factors lead to less-than-ideal configurations, so this can occur.

The problem does occur if you use the ISA Server to support RSA SecurID authentication, rather than using IIS. When you change RSA authentication from IIS to ISA, Exchange ActiveSync will fail, and mobile devices will be unable to synchronize with Microsoft Exchange Server 2003.

To solve this, reconfigure your organization to use IIS to handle RSA SecurID authentication for ActiveSync traffic. If this isn't possible, use a newer version of ISA Server or invest in a third-party add-on product.

SSL-related ActiveSync errors

ActiveSync must be able to access the Exchange virtual directory located on the back-end server containing users' mailboxes to operate properly. However, ActiveSync cannot access the virtual directory if the back-end server requires SSL encryption, or if a forms-based authentication is enabled. When these conditions exist, three distinct events are displayed in the server's Application log. Depending on the server's configuration, you may receive one or a combination of all of the following events:

  • Event Type: Error
    Event Source: Server ActiveSync
    Event Category: None
    Event ID: 3029
    Description: The mailbox server [server name] has its [virtual directory name] virtual directory set to require SSL. Exchange
  • Event Type: Error
    Event Source: Server ActiveSync
    Event Category: None
    Event ID: 3030
    Description: The mailbox server [server name] has forms based authentication enabled on its virtual server. Exchange ActiveSync cannot access the server when Forms based authentication is enabled.
  • Event Type: Error
    Event Source: Server ActiveSync
    Event Category: None
    Event ID: 3031
    Description: The mailbox server [server name] does not allow "Negotiate" authentication to its [virtual directory name] virtual directory. Exchange ActiveSync can only access the server using this authentication scheme.

The best solution is to implement a front-end/back-end configuration. But if this isn't an option, you can perform a workaround by editing the registry.

This procedure should only be performed on an Exchange Server 2003 containing user mailboxes. An organization must not have a front-end server installed. Microsoft strongly advises that you use a front-end/back-end server configuration for security reasons. And, while this workaround works, your Exchange Server organization security can't be guaranteed.

To implement a front-end/back-end configuration:

  1. Open the IIS Manager and navigate through the console tree to: Web Sites\Default Web Site\Exchange.
  2. Right click on the Exchange virtual directory and select the All Tasks -> Save Configuration to a File command from the menu. IIS will prompt you to name the file. Name the file ExchangeVDir and click OK.
  3. Right click on the Web Site container, and choose New -> Web Site (from file).
  4. Use the dialog box to import the new file. You should receive an error message indicating that the virtual directory already exists. Use the Alias box to enter a new name for the virtual directory that you're creating. Microsoft suggests using the name \Exchange-OMA.
  5. Right click on the new virtual directory, and choose Properties from the menu. The IIS Manager console will display the new virtual directory's properties sheet.
  6. Navigate to the Directory Security tab and click Edit in the Authentication and Access Control section. Verify that only the Integrated Windows Authentication and the Basic Authentication checkboxes are selected.
  7. Click OK, and then select Edit, in the IP Address and Domain Name Restrictions section.
  8. Choose Denied Access, and then click on Add. When prompted, enter the IP address of the server that you're configuring.
  9. Click OK, and then select Edit under the Secure Communications section.
  10. Verify that the Require Secure Communications (SSL) checkbox is not selected, and click OK.
  11. Click OK and close the IIS Manager console.

Now you can edit the server's registry so that the server will treat the new virtual directory as the Exchange virtual directory. To do so:

  1. Open the Registry Editor and navigate through the console tree to: HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\MasSync\Parameters.
  2. Right click on the Parameters container, and choose New -> String Value from the menu.
  3. Name the new string value ExchangeVDir. Note: this is case sensitive.
  4. Once you've created this value, right click on it, and choose Modify. You must set the value's data to contain the name of the new virtual directory you have created. Because you used Microsoft's recommended name, the value will be \Exchange-OMA.
  5. Click OK and close the Registry Editor.
  6. Restart the IIS Admin Service. You can accomplish this by opening the Service Control Manager, right clicking on the IIS Admin service and choosing Restart.

If you implement a front-end/back-end configuration, a highly recommended procedure, you must stop the IIS Admin service and delete both the ExchangeVDIr registry key and the Exchange-OMA virtual directory.

ABOUT THE AUTHOR:  Brien M. Posey, MCSE, is a Microsoft Most Valuable Professional for his work with Exchange Server, and has previously received Microsoft's MVP award for Windows Server and Internet Information Server (IIS). Brien has served as CIO for a nationwide chain of hospitals and was once responsible for the Department of Information Management at Fort Knox. As a freelance technical writer, Brien has written for Microsoft, TechTarget, CNET, ZDNet, MSD2D, Relevant Technologies and other technology companies. You can visit Brien's personal Web site at

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