Topic Last Modified: 2009-04-30
Problems may occur if you customize the Active Directory schema for Microsoft Exchange Server 2007.
For example, the maximum value (RangeUpper attribute) of the extensionAttribute1 attribute may be changed from 1024 to 20480 by using the AdsiEdit.msc tool or any other schema editors. When you move a mailbox from Exchange Server 2003 to Exchange Server 2007 after this change is made, you may receive the following error message:
Summary: 1 item(s). 0 succeeded, 1 failed.
Elapsed time: 00:00:01
Error: CustomAttribute1 is too long: maximum length is 1024, actual length is 1348.
Therefore, we recommend that you do not customize the Active Directory schema for Exchange 2007.