An event sink that is registered against a mailbox does not work in Exchange Server 2003 (821757)

CAUSE

This problem occurs if the user's mailbox contains a forward slash (/) character in the mailNickname property. For example, this problem occurs if the user's mailbox name is similar to User/Name. In this scenario, the registered event sink cannot obtain a valid URL for an item in the user's mailbox.

This problem might occur when one or more of the following conditions are true:

• You configure a mailbox name that contains a forward slash character in Microsoft Exchange Server 5.5 and then upgrade to Exchange 2003.
  
  Note A forward slash character is permitted in an Exchange 5.5 mailbox name.
• You add a forward slash character to a user's mailNickname property by using the ADSI Edit tool.
• You add a forward slash character to a user's e-mail alias by using the Active Directory Users and Computers tool.

Exchange 2003 should replace the forward slash character with an underscore (_) character. When the mailbox name contains a forward slash character, the URL to an item in that mailbox is not valid.