That is a different thing. Google Chrome with version 8 and later introduced a Chrome PDF Viewer that is incompatible with Adobe's plugin. The Web Report Viewer uses the Adobe Reader's plug-in for the print functionality. Thus in order for the printing to work, you have to enable the Adobe's plug-in from chrome://plugins/ page, which automatically disables chrome plug-in as they are mutually exclusive.
You would be happy to know that we were able to utilize the Chrome PDF Viewer for printing as well and this functionality would also be available in the upcoming service pack.
the Telerik team
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