Before changing the registry, please run the product installer as suggested in the Telerik Reporting Toolbox items are missing
KB article, and check for any listed problems.
Keep in mind that major Telerik Reporting versions can co-exist on the machine, but you will find enabled for work in VS only the latest version.
The Toolbox is loaded with Telerik Reporting items of the latest available version installed on the machine. If the opened in VS project is not upgraded to that version, the item will not appear in the Toolbox. If you run the Upgrade Wizard in the solution, the project will be upgraded to Telerik Reporting Q1 2014 and the Toolbox will be populated with items.
If you need further help with the Toolbox items, please open a support ticket and send us the created log file.
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