If you simply search on the error message within the subject then the best point of it is you get many references on how to resolve this issue. Going back to root cause of the problem is that number of people have reported problems using the ActiveX print control in the report viewer after installing Microsoft Update 956391 having users receive the error " Unable to load client print control " when clicking on the print icon in the report viewer toolbar. The reason that Microsoft has deactivated...(
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Read the complete post at http://sqlserver-qa.net/blogs/bi/archive/2009/06/30/sql-server-reporting-services-issue-unable-to-load-client-print-control.aspx