You cannot use ActiveSync on a mobile device to synchronize with a mailbox in an Exchange Server 2003 domain by using an associated user account in an NT4 domain

Consider the following scenario:

• You have a computer that is running Microsoft Exchange Server 2003.
• You use ActiveSync on a mobile device to synchronize with a mailbox in an Exchange Server 2003 domain by using an associated external user account in an NT4 domain.

In this scenario, the synchronization fails and the following error messages are displayed on the mobile device:

Microsoft supports ActiveSync from a mobile device to a mailbox that is attached to a user that resides in an Exchange Server 2003 environment. However, synchronization from a mobile device to mailboxes that reside in an Exchange Server 2003 environment by using a user account that resides in an NT4 environment has not been tested. Therefore, Microsoft does not support this functionality.

For more information, click the following article numbers to view the articles in the Microsoft Knowledge Base:

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