Microsoft Expression Web Service Pack 1 delivers important customer-requested stability and performance improvements, while incorporating further enhancements to user security. This service pack also includes all of the updates released for Expression Web prior to December of 2007. You can get a more complete description of SP1, including a list of issues that were fixed, in the Microsoft Knowledge Base article 937163: Description of the Microsoft Expression Web Service Pack 1.

Link:
http://www.microsoft.com/downloads/…

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