Tim Mackey's Weblog

The full error i got was below:

Error    35    The type 'CrystalDecisions.Shared.ExportFormatType' exists in both 
'c:\Windows\assembly\GAC\CrystalDecisions.Shared\9.1.5000.0__692fbea5521e1304\CrystalDecisions.Shared.dll' and 
'c:\Windows\assembly\GAC_MSIL\CrystalDecisions.Shared\10.2.3600.0__692fbea5521e1304\CrystalDecisions.Shared.dll'   

The reason is because version 9 and 10 of crystal reports are installed on my dev box and VS needed help deciding which one to use.  the fix was to specify the exact assembly binding to use in web.config, as follows:

	<runtime>
		<assemblyBinding xmlns="urn:schemas-microsoft-com:asm.v1">
			<dependentAssembly>
				<assemblyIdentity name="CrystalDecisions.CrystalReports.Engine" publicKeyToken="692fbea5521e1304" />
				<bindingRedirect oldVersion="9.1.5000.0" newVersion="10.2.3600.0"/>
			</dependentAssembly>
			<dependentAssembly>
				<assemblyIdentity name="CrystalDecisions.CrystalReports.Shared" publicKeyToken="692fbea5521e1304" />
				<bindingRedirect oldVersion="9.1.5000.0" newVersion="10.2.3600.0"/>
			</dependentAssembly>
			<dependentAssembly>
				<assemblyIdentity name="CrystalDecisions.Shared" publicKeyToken="692fbea5521e1304" />
				<bindingRedirect oldVersion="9.1.5000.0" newVersion="10.2.3600.0"/>
			</dependentAssembly>
		</assemblyBinding>
	</runtime>

thanks to rick ersek for the solution.