Silverlight 4 Beta documentation is availble in two version; First being accessible on MSDN via Silverlight Developer Center along with resources still offered for Silverlight 3. Or as a standalone CHM (Compiled HTML Help file) format for offline viewing. Users will first have to extract the contents of the archive in order to get the documentation. Microsoft additionally informs that unblocking the CHM file might also be necessary. Customers will need to right click the file and select Unblock from the options at the bottom.

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